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Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2018	Feb. 22, 2019	Jun. 30, 2018
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Trading Symbol	CHRS
Entity Registrant Name	Coherus BioSciences, Inc.
Entity Central Index Key	0001512762
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Common Stock, Shares Outstanding		69,259,704
Entity Public Float			$ 632.1

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 72,356	$ 126,911
Restricted cash	50	60
Inventory	1,659
Prepaid manufacturing	7,906	14,969
Other prepaid assets (includes related parties of $0 and $908 as of December 31, 2018 and 2017, respectively)	2,379	3,395
Other assets	83	142
Total current assets	84,433	145,477
Property and equipment, net	6,660	12,773
Inventory, non-current	4,012
Intangible assets	2,620	2,620
Goodwill	943	943
Restricted cash, non-current	785	785
Other assets, non-current	14	13
Total assets	99,467	162,611
Current liabilities:
Accounts payable	15,294	15,481
Accounts payable - related parties		233
Accrued compensation	10,540	2,074
Accrued liabilities (includes related parties of $0 and $510 as of December 31, 2018 and 2017, respectively)	7,008	6,976
Contingent consideration, current		3,290
Other current liabilities	419	341
Total current liabilities	33,261	28,395
Contingent consideration, non-current	60
Convertible notes	77,319	76,206
Convertible notes - related parties	25,773	25,402
Other liabilities, non-current	1,645	2,073
Total liabilities	138,058	132,076
Commitments and contingencies (Note 8)
Stockholders’ equity (deficit):
Preferred stock, $0.0001 par value; Shares authorized: 5,000,000; Shares issued and outstanding: no shares at December 31, 2018 and 2017.
Common stock, $0.0001 par value; Shares authorized: 300,000,000; Shares issued and outstanding: 68,302,681 and 59,840,467 at December 31, 2018 and 2017, respectively	7	6
Additional paid-in capital	946,515	808,060
Accumulated other comprehensive loss	(282)	(750)
Accumulated deficit	(984,831)	(775,492)
Total Coherus stockholders' equity (deficit)	(38,591)	31,824
Non-controlling interest		(1,289)
Total stockholders' equity (deficit)	(38,591)	30,535
Total liabilities and stockholders’ equity (deficit)	$ 99,467	$ 162,611

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Prepaid assets, related parties	$ 0	$ 908
Accrued liabilities, related parties	$ 0	$ 510
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	68,302,681	59,840,467
Common stock, shares outstanding	68,302,681	59,840,467

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue:
Collaboration and license revenue	$ 0	$ 1,556	$ 189,476
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Other revenue	$ 0	$ 0	$ 630
Total revenue	0	1,556	190,106
Operating expenses:
Research and development (includes related party of $1,609, $8,199 and $34,705 for the years ended December 31, 2018, 2017 and 2016, respectively)	110,239	162,389	254,440
Selling, general and administrative (includes related party of $181, $62 and $178 for the years ended December 31, 2018, 2017 and 2016, respectively)	94,177	71,303	51,597
Total operating expenses	204,416	233,692	306,037
Loss from operations	(204,416)	(232,136)	(115,931)
Interest expense (includes related party of $2,421, $2,388 and $1,980 for the years ended December 31, 2018, 2017 and 2016, respectively)	(9,684)	(9,552)	(7,980)
Other income (expense), net	4,691	3,402	(3,877)
Net loss	(209,409)	(238,286)	(127,788)
Net loss attributable to non-controlling interest	70	116	451
Net loss attributable to Coherus	$ (209,339)	$ (238,170)	$ (127,337)
Net loss per share attributable to Coherus, basic and diluted	$ (3.22)	$ (4.48)	$ (3.04)
Weighted-average number of shares used in computing net loss per share attributable to Coherus, basic and diluted	65,034,827	53,133,620	41,912,300

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Selling, general and administrative expenses from transactions with related party	$ 181	$ 62	$ 178
Interest expense from transactions with related party	2,421	2,388	1,980
Research and Development Expense
Research and development from transactions with related party	$ 1,609	$ 8,199	$ 34,705

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (209,409)	$ (238,286)	$ (127,788)
Other comprehensive loss:
Foreign currency translation adjustments, net of tax	468	(120)	(229)
Comprehensive loss	(208,941)	(238,406)	(128,017)
Comprehensive loss attributable to non-controlling interest	70	116	451
Comprehensive loss attributable to Coherus	$ (208,871)	$ (238,290)	$ (127,566)

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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+ Details

Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock Offering	Private Placement	2017 Bonus Payout	Common Stock	Common Stock Common Stock Offering	Common Stock Private Placement	Common Stock Restricted Stock Units	Common Stock 2017 Bonus Payout	Additional Paid-In Capital	Additional Paid-In Capital Common Stock Offering	Additional Paid-In Capital Private Placement	Additional Paid-In Capital 2017 Bonus Payout	Accumulated Other Comprehensive Loss	Accumulated Deficit	Total Coherus Stockholder Equity (Deficit)	Total Coherus Stockholder Equity (Deficit) Common Stock Offering	Total Coherus Stockholder Equity (Deficit) Private Placement	Total Coherus Stockholder Equity (Deficit) 2017 Bonus Payout	Noncontrolling Interest
Beginning Balances at Dec. 31, 2015	$ (6,929)				$ 4					$ 404,175				$ (401)	$ (409,985)	$ (6,207)				$ (722)
Beginning Balances, Shares at Dec. 31, 2015					39,005,589
Issuance of common stock		$ 123,567				$ 1					$ 123,566						$ 123,567
Issuance of common stock, Shares						6,040,987
Issuance of common stock upon exercise of stock options	3,312									3,312						3,312
Issuance of common stock upon exercise of stock options, Shares					761,587
Stock-based compensation expense	27,421									27,421						27,421
Cumulative translation adjustment	(229)													(229)		(229)
Distributions to non-controlling interest	(451)																			(451)
Net loss attributable to Coherus	(127,337)														(127,337)	(127,337)
Ending Balances at Dec. 31, 2016	19,354				$ 5					558,474				(630)	(537,322)	20,527				(1,173)
Ending Balances, shares at Dec. 31, 2016					45,808,163
Issuance of common stock		131,849	$ 81,810	$ 2,668			$ 1				131,849	$ 81,809	$ 2,668				131,849	$ 81,810	$ 2,668
Issuance of common stock, Shares						6,220,901	7,332,220	14,750	301,455
Offering costs associate with common stock offering and private placements	(619)									(619)						(619)
Issuance of common stock upon exercise of stock options	482									482						482
Issuance of common stock upon exercise of stock options, Shares					162,978
Stock-based compensation expense	33,397									33,397						33,397
Cumulative translation adjustment	(120)													(120)		(120)
Distributions to non-controlling interest	(116)																			(116)
Net loss attributable to Coherus	(238,170)														(238,170)	(238,170)
Ending Balances at Dec. 31, 2017	$ 30,535				$ 6					808,060				(750)	(775,492)	31,824				(1,289)
Ending Balances, shares at Dec. 31, 2017	59,840,467				59,840,467
Issuance of common stock		$ 102,261				$ 1					$ 102,260						$ 102,261
Issuance of common stock, Shares						7,747,778		61,804
Offering costs associated with common stock offering	$ (473)									(473)						(473)
Issuance of common stock upon exercise of stock options	$ 2,153									2,153						2,153
Issuance of common stock upon exercise of stock options, Shares	477,019				477,019
Stock-based compensation expense	$ 34,984									34,984						34,984
Issuance of common stock upon ESPP purchase	1,591									1,591						1,591
Issuance of common stock upon ESPP purchase, Shares					175,613
Cumulative translation adjustment	468													468		468
Distributions to non-controlling interest	(2,130)									(2,060)						(2,060)				(70)
Purchase of the remaining non-controlling interest	1,359																			$ 1,359
Net loss attributable to Coherus	(209,339)														(209,339)	(209,339)
Ending Balances at Dec. 31, 2018	$ (38,591)				$ 7					$ 946,515				$ (282)	$ (984,831)	$ (38,591)
Ending Balances, shares at Dec. 31, 2018	68,302,681				68,302,681

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating activities
Net loss	$ (209,409)	$ (238,286)	$ (127,788)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,235	3,398	2,996
Remeasurement of fair-value contingent consideration	(3,230)	(2,260)	4,305
Non-cash accretion of discount on marketable securities	(301)	(156)
Non-cash interest expense from amortization of debt discount	1,484	1,352	1,041
Provision for other receivables			(1,300)
Stock-based compensation expense	34,797	33,397	27,421
Non-cash bonus payment settled in common stock		2,668
Non-cash manufacturing postponement fee settled in common stock		4,125
Loss (gain) on disposal of property and equipment		51	(6)
Impairment of property and equipment	3,861	558
Changes in operating assets and liabilities:
Receivables from collaboration and license agreement		1,859	(299)
Inventory	(5,484)
Prepaid manufacturing	7,063	7,788	(16,119)
Other prepaid assets	1,016	8,170	19,246
Other assets	130	2,844	1,111
Other assets, non-current	(1)		88
Accounts payable	(301)	(3,810)	(4,965)
Accounts payable - related parties	(233)	(644)	(2,671)
Accrued compensation	8,466	(4,871)	2,279
Accrued liabilities	(9)	(14,162)	1,674
Other liabilities	78	83	65
Deferred revenue		(1,562)	(93,236)
Advance payments under license agreements		(1,070)	(260)
Contingent liability to collaborator			(66,255)
Other liabilities, non-current	(428)	242	128
Net cash used in operating activities	(159,266)	(200,286)	(252,545)
Investing activities
Purchases of property and equipment	(789)	(4,573)	(6,515)
Purchases of investments in marketable securities	(42,869)	(74,344)
Proceeds from maturities of investments in marketable securities	43,170	74,500
Purchase of non-controlling interest related to InteKrin Russia	(300)
Purchase of non-controlling interest related to InteKrin Russia - related party	(400)
Net cash used in investing activities	(1,188)	(4,417)	(6,515)
Financing activities
Proceeds from issuance of convertible notes			75,000
Proceeds from issuance of convertible notes - related parties			25,000
Proceeds from private placement		75,000
Proceeds from common stock offering, net of underwriters discounts, commissions and offering costs	101,748	131,305	123,606
Payments of convertible notes issuance costs			(739)
Proceeds from ESPP purchase	1,591
Proceeds from issuances of common stock upon exercise of stock options	2,082	482	3,312
Net cash provided by financing activities	105,421	206,787	226,179
Effect of exchange rate changes in cash, cash equivalents and restricted cash	468	(120)	(398)
Net increase (decrease) in cash, cash equivalents and restricted cash	(54,565)	1,964	(33,279)
Cash, cash equivalents and restricted cash at beginning of period	127,756	125,792	159,071
Cash, cash equivalents and restricted cash at end of period	73,191	127,756	125,792
Supplemental disclosure of cash flow information
Cash paid for interest	8,200	8,200	6,939
Supplemental disclosures of noncash investing and financing activities
Purchase of property and equipment in accounts payable and accrued liabilities	194	(430)	507
Non-cash non-controlling interest reflected in additional paid in capital	1,359
Common stock offering costs in accounts payable and accrued liabilities	$ (39)	75	$ 39
Manufacturing services settled in common stock		$ 6,810

Organization and Operations

12 Months Ended

Dec. 31, 2018

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Organization and Operations

1.	Organization and Operations

Description of the Business

The Company is a commercial-stage biotherapeutics company, focused on the global biosimilar market. Biosimilars are a class of protein-based therapeutics with high similarity to approved originator products on the basis of various structural, physicochemical and biological properties, as well as in terms of safety and efficacy. The Company’s headquarters and laboratories are located in Redwood City, California and in Camarillo, California, respectively.

On September 25, 2018, the Company received regulatory approval for the marketing of UDENYCA™ (pegfilgrastim-cbqv), a biosimilar to Neulasta, a long-acting granulocyte-colony stimulating factor, from the European Commission, and received regulatory approval for UDENYCA™ from the U.S. Food and Drug Administration (“FDA”) on November 2, 2018. The Company initiated U.S. sales of UDENYCA™ on January 3, 2019.

Need to Raise Additional Capital

As of December 31, 2018, the Company had an accumulated deficit of $984.8 million and cash and cash equivalents of $72.4 million. In 2018, the Company issued and sold 1,799,504 shares of common stock at a weighted average price of $12.14 per share through its ATM Offering Program and received total net proceeds of $21.0 million after deducting the underwriting discounts and commissions and offering expenses. In May 2018, the Company completed an underwritten public offering of 5,948,274 shares of its common stock at a price to the public of $14.50 per share, which includes the closing of the full exercise of the underwriters’ option to purchase an additional 775,861 shares of common stock. The Company received net proceeds from the offering of $80.8 million, after deducting the underwriting discounts and commissions and offering expenses (see Note 9). The Company also entered into a credit agreement (the “Credit Agreement”) with affiliates of Health Royalty Partners consisting of a six-year term loan facility for an aggregate principal of $75.0 million in January 2019. The Company believes that its current available cash and cash equivalents, the proceeds from the Credit Agreement of $73.1 million, net of offering and original issue discount costs, and cash collected from UDENYCA™ sales will be sufficient to fund its planned expenditures and meet the Company’s obligations for at least 12 months following its financial statement issuance date. The Company may need to raise additional funds in the future; however there can be no assurance that such efforts will be successful or that, in the event that they are successful, the terms and conditions of such financing will be favorable. If the Company is unable to obtain adequate financing when needed, it may have to delay, reduce the scope of or suspend one or more of its clinical trials, or research and development programs.

Basis of Presentation and Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Basis of Presentation and Summary of Significant Accounting Policies

2.	Basis of Presentation and Summary of Significant Accounting Policies

Basis of Consolidation

The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”). The accompanying consolidated financial statements include the accounts of Coherus and its wholly owned subsidiaries as of December 31, 2018: Coherus Intermediate Corp, InteKrin Therapeutics Inc. (“InteKrin”) and InteKrin’s subsidiary, InteKrin Russia. In September 2018, InteKrin acquired the remainder of InteKrin Russia’s non-controlling interest of 17.5% for $0.7 million in cash. Unless otherwise specified, references to the Company are references to Coherus and its consolidated subsidiaries. All intercompany transactions and balances have been eliminated upon consolidation.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts and disclosures reported in the financial statements. Management uses significant judgment when making estimates related to its stock-based compensation, valuation of deferred tax assets, impairment of goodwill and long-lived assets, the valuation of acquired intangible assets, valuation and reserves for inventory, clinical trial accruals, revenue recognition periods, contingent consideration, convertible notes valuation, as well as certain accrued liabilities. Management bases its estimates on historical experience and on other various assumptions that are believed to be reasonable under the circumstances. These estimates form the basis for making judgments about the carrying values of assets and liabilities when these values are not readily apparent from other sources. Accounting estimates and judgements are inherently uncertain and the actual results could differ from these estimates.

Foreign Currency

The functional currency of InteKrin Russia, which the Company acquired in February 2014, is the Russian Ruble. Accordingly, the financial statements of this subsidiary are translated into U.S. dollars using appropriate exchange rates. Unrealized gains or losses on translation are recognized in accumulated other comprehensive loss in the consolidated balance sheet.

For the years ended December 31, 2018, 2017 and 2016, the foreign exchange gains and losses recorded in other income (expense), net in the consolidated statements of operations were a net loss of $571,000, a net gain of $52,000 and a net loss of $53,000, respectively.

Segment Reporting and Customer Concentration

The Company operates and manages its business as one reportable and operating segment, which is the business of developing and commercializing biosimilar products and, as part of the InteKrin acquisition, small molecules. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for purposes of allocating resources and evaluating financial performance. Long-lived assets are primarily maintained in the United States of America.

The following table summarizes revenue by geographic region (in thousands):

	Year Ended December 31,
	2018		2017		2016
United States	$	—	$	—	$	188,292
Rest of world		—		1,556		1,814
Total revenue	$	—	$	1,556	$	190,106

Customer Concentration

Customers whose collaboration and license revenue accounted for 10% or more of total revenues were as follows:

	Year Ended December 31,
	2018	2017			2016
Baxalta	N/A	N/A				99	%
Daiichi Sankyo	N/A		100	%	*

*less than 10%

Cash and Cash Equivalents

Cash, cash equivalents and restricted cash are comprised of cash and highly liquid investments with remaining maturities of 90 days or less at the date of purchase. The Company limits cash investments to financial institutions with high credit standings; therefore, management believes that there is no significant exposure to any credit risk in the Company’s cash, cash equivalents and restricted cash.

The following table provides a reconciliation of cash, cash equivalents and restricted cash within the consolidated balance sheets and which, in aggregate, represent the amount reported in the consolidated statements of cash flows.

	December 31,		December 31,
	2018		2017
Cash and cash equivalents	$	72,356	$	126,911
Restricted cash		50		60
Restricted cash - non-current		785		785
Total cash, cash equivalents and restricted cash	$	73,191	$	127,756

Restricted cash consists of cash held in money market accounts at banks. The restricted cash is used as collateral against the Company’s corporate credit cards and is classified as current; restricted cash non-current is held to cover the standby letter of credit issued by the Company’s landlord to drawdown on in the event the facility lease is breached (see Note 8).

Investments in Marketable Securities

Management determines the appropriate classification of investments in marketable securities at the time of purchase based upon management’s intent with regards to such investments and reevaluates such designation as of each balance sheet date. All investments in marketable securities are held as “available-for-sale” and are carried at the estimated fair value as determined based upon quoted market prices or pricing models for similar securities.

The Company classifies investments in marketable securities as short-term when they have remaining contractual maturities of one year or less from the balance sheet date. Unrealized gains and losses are excluded from earnings and are reported as a component of accumulated comprehensive income (loss). Realized gains and losses and declines in value judged to be other than temporary, if any, on available-for-sale securities are included in other income (expense), net, based on specific identification method. The Company started investing in marketable securities in 2017. For the years ended December 31, 2018 and 2017, interest income from marketable securities was $1.4 million and $0.8 million, respectively.

Concentration of Credit Risk

The Company’s financial instruments that are exposed to concentration of credit risk consist primarily of cash, cash equivalents and restricted cash. The Company maintains its cash in bank accounts, which at times exceed federally insured limits. The Company attempts to minimize the risks related to cash, cash equivalents and restricted cash by investing in money markets with a broad and diverse range of financial instruments. The investment portfolio is maintained in accordance with the Company’s investment policy, which defines allowable investments, specifies credit quality standards and limits the credit exposure of any single issuer. The Company also maintains restricted cash in money market funds that invest primarily in U.S. Treasury securities. The Company has not recognized any losses from credit risks on such accounts during any of the periods presented. The Company believes it is not exposed to significant credit risk on its cash and money market funds.

The Company entered into a strategic commercial supply agreement with KBI Biopharma (“KBI”) for the supply of UDENYCA™. The Company currently has not engaged back-up suppliers or vendors for this single-sourced service. If KBI is not able to manufacture the supply needed in the quantities and timeframe required, the Company may not be able to supply the product in a timely manner.

Fair Value of Financial Instruments

Fair value accounting is applied to all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis.

Inventory

Prior to the regulatory approval of the product candidates, the Company incurred expenses for the manufacture of drug product that could potentially be available to support the commercial launch of its products. The Company began to capitalize inventory costs associated with UDENYCA™ after receiving regulatory approval for UDENYCA™ in November 2018 when it was determined that the inventory had a probable future economic benefit.

Inventory is stated at the lower of cost or estimated net realizable value with cost determined under the first-in first-out method. Inventory costs include third-party contract manufacturing, third-party packaging services, freight, labor costs for personnel involved in the manufacturing process, and indirect overhead costs. The Company primarily uses actual costs to determine the cost basis for inventory. The determination of whether inventory costs will be realizable requires management review of the expiration dates of the Company’s product UDENYCA™ compared to its forecasted sales. If actual market conditions are less favorable than projected by management, write-downs of inventory may be required which would be recorded as cost of sales in the consolidated statement of operations.

Property and Equipment

Property and equipment is stated at cost less accumulated depreciation and amortization. Maintenance and repairs are charged to expense as incurred, and costs of improvements are capitalized. Depreciation and amortization is recognized using the straight-line method over the following estimated useful lives:

Computer equipment and software		3 years
Furniture and fixtures		5 years
Machinery and equipment		5 years
Leasehold improvements		Shorter of lease term or useful life

Impairment of Long Lived Assets and Acquired Intangible Asset

The Company reviews long-lived assets, including property and equipment, and indefinite-lived intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be fully recoverable. An impairment loss would be recognized when the estimated undiscounted future cash flows expected to result from the use of the asset and its eventual disposition is less than its carrying amount. Impairment, if any, is measured as the amount by which the carrying value of a long-lived asset exceeds its fair value. For the years ended December 31, 2018, 2017 and 2016, the Company recorded an impairment of property and equipment of $3.9 million, $558,000 and $0, respectively, in research and development within the statement of operations.

Acquired in-process research and development (“IPR&D”) represents the fair value assigned to research and development assets that have not reached technological feasibility. The Company reviews amounts capitalized as acquired IPR&D for impairment at least annually, and whenever events or changes in circumstances indicate that the carrying value of the assets might not be recoverable. If the carrying value of the acquired IPR&D exceeds its fair value, then the intangible asset is written-down to its fair value. As of December 31, 2018, there have been no such impairments. Once the product candidate derived from the indefinite-lived intangible asset has been developed and commercialized, the useful life will be determined, and the carrying value of the finite-lived asset will be amortized prospectively over the estimated useful life. Alternatively, if the product candidate is abandoned, the carrying value of the intangible will be charged to research and development expense.

Goodwill

Goodwill represents the excess of the purchase price over the fair value of the net tangible and intangible assets acquired. The Company tests goodwill for impairment at least annually or more frequently if events or changes in circumstances indicate that this asset may be impaired. The goodwill test is based on our single operating segment and reporting unit structure.

The Company compares the fair value of its reporting unit to its carrying value. If the carrying value of the net assets assigned to the reporting unit exceeds the fair value of the reporting unit, then the Company would need to determine the implied fair value of the reporting unit’s goodwill. If the carrying value of the reporting unit’s goodwill exceeds its implied fair value, then the Company would record an impairment loss equal to the difference. No goodwill impairment was identified through December 31, 2018.

Derivative Liability

The Company has a derivative liability related to the contingent consideration associated with the acquisition of InteKrin in 2014. There were two contingent payments payable upon the achievement of certain events: (i) the completion of the first dosing of a human subject in the first Phase 2 clinical trial for InteKrin, (“Earn-Out Payment”) and (ii) upon the execution of any license, sublicense, development, collaboration, joint venture, partnering or similar agreement between the Company and the third party (“Compound Transaction Payment”). The derivative related to the contingent consideration is accounted for as a liability and remeasured to fair value as of each balance sheet date and the related remeasurement adjustment is recognized as other income (expense), net in the consolidated statements of operations. The Company determined the fair value of the two contingent consideration scenarios (the Earn-Out Payment and the Compound Transaction Payment) using a probability-weighted discounted cash flow approach. A probability-weighted value was determined by summing the probability of achieving a contingent payment threshold by the respective contingent payments. The expected cash flows were discounted at a rate selected to capture the risk of achieving the contingent payment thresholds and earning the contingent payment. This risk is comprised of InteKrin’s continued development, a specific risk factor associated with meeting the contingent consideration threshold and related payout, and counterparty risk associated with the payment of the contingent consideration.

Accrued Research and Development Expense

Clinical trial costs are a component of research and development expense. The Company accrues and expenses clinical trial activities performed by third parties based upon actual work completed in accordance with agreements established with clinical research organizations and clinical sites. The Company determines the actual costs through monitoring patient enrollment, discussions with internal personnel and external service providers regarding the progress or stage of completion of trials or services and the agreed-upon fee to be paid for such services.

Revenue Recognition

The Company adopted ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) (ASU 2014-09), ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations; ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing; and ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients, (collectively, the “New Revenue Standard”) on January 1, 2018 using the modified retrospective method.

The Company did not have any sources of revenue or active revenue arrangements upon adoption of the New Revenue Standard, therefore, no adjustment to its retained earnings was required. If, and when, the Company initiates product sales or enters into a new revenue arrangement, the Company will apply the New Revenue Standard accordingly. On September 25, 2018, the Company received regulatory approval for the marketing of UDENYCA™ from the European Commission, and received regulatory approval from the FDA on November 2, 2018. The Company initiated U.S. sales of UDENYCA™ on January 3, 2019, which will be accounted for under Topic 606 Revenue from Contracts with Customers in 2019.

Prior to the adoption of the New Revenue Standard, the Company recognized revenue in accordance with Accounting Standards Codification (ASC) 605, Revenue Recognition when persuasive evidence of an arrangement existed; transfer of technology had been completed, services had been performed or products had been delivered; the fee was fixed and determinable; and collection was reasonably assured.

For revenue agreements with multiple elements, the Company identified the deliverables included within the agreement and evaluated which deliverables may represent separate units of accounting based on the achievement of certain criteria, including whether the delivered element had stand-alone value to the collaborator. Deliverables under the arrangement were considered a separate unit of accounting if (i) the delivered item had value to the customer on a standalone basis and (ii) if the arrangement included a general right of return relative to the delivered item and delivery or performance of the undelivered items were considered probable and substantially within the Company’s control.

The Company determined how to allocate arrangement consideration to identified units of accounting based on the selling price hierarchy provided under the relevant guidance. The selling price used for each unit of accounting was based on vendor-specific objective evidence, if available, third party evidence if vendor-specific objective evidence was not available or estimated selling price if neither vendor-specific nor third-party evidence was available. Management was required to exercise considerable judgment in determining whether a deliverable was a separate unit of accounting and in estimating the selling prices of identified units of accounting under its agreements.

Upfront payments received in connection with licenses of the Company’s technology rights were deferred if facts and circumstances dictated that the license did not have stand-alone value. Such payments were recognized as license revenue over the estimated period of performance, which was generally consistent with the terms of the research and development obligations contained in the specific collaboration and license agreement. The Company regularly reviewed the estimated period of performance based on the progress made under each arrangement. Amounts received as funding of research and development activities were recognized as revenue if the collaboration arrangement involved the sale of the Company’s research or development services. However, such funding was recognized as a reduction in research and development expense when the Company engaged in a research and development project jointly with another entity, with both entities participating in project activities and sharing costs and potential benefits of the arrangement.

Payments that were contingent upon the achievement of a substantive milestone were recognized in their entirety in the period in which the milestone was achieved, assuming all other revenue recognition criteria were met. A milestone was defined as an event that could only be achieved based on the Company’s performance where there was substantive uncertainty about whether the event would be achieved at the inception of the arrangement. Events that were contingent upon on the passage of time or counterparty performance were not considered milestones under accounting guidance. The Company’s evaluation included an assessment of whether (a) the consideration was commensurate with either (1) the Company’s performance to achieve the milestone, or (2) the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the Company’s performance to achieve the milestone, (b) the consideration related solely to past performance and (c) the consideration was reasonable relative to all of the deliverables and payment terms within the arrangement. The Company evaluated factors such as the scientific, regulatory, commercial and other risks that must be overcome to achieve the respective milestone, the level of effort and investment required to achieve the respective milestone and whether the milestone consideration was reasonable relative to all deliverables and payment terms in the arrangement in making this assessment.

Other contingent payments in which a portion of the payment was refundable or adjustable based on future performance or non-performance (e.g., through a penalty or claw-back provision) were not considered to relate solely to the Company’s past performance, and therefore, not considered substantive. Non-substantive contingent payments were classified as deferred revenue if they were ultimately expected to result in revenue recognition. The Company recognized non-substantive contingent payments over the remaining estimated period of performance once the specific objective was achieved. Any portion of the non-substantive contingent payments, which may have been required to be refunded to the collaborator, were not included in deferred revenue but instead were reflected as a contingent liability to collaborator on the consolidated balance sheets.

Contingent payments associated with the achievement of specific objectives in certain contracts that were not considered substantive because the Company did not contribute effort to the achievement of such milestones were recognized as revenue upon achievement of the objective, as long as there were no undelivered elements remaining and no continuing performance obligations by the Company, assuming all other revenue recognition criteria were met.

Research and Development Expense

Research and development costs are charged to expense as incurred. Research and development expense includes, among other costs, salaries and other personnel-related costs, consultant fees, preclinical costs, cost to manufacture drug candidates, clinical trial costs and supplies, laboratory supply costs and facility-related costs. Costs incurred under agreements with third parties are charged to expense as incurred in accordance with the specific contractual performance terms of such agreements. Third-party costs include costs associated with manufacturing drug candidates, preclinical and clinical support activities. In certain cases, amounts received as reimbursement for research and development activities from the Company’s collaborators are recognized as a reduction in research and development expense when the Company engages in a research and development project, jointly with another party, with both parties incurring costs while actively participating in project activities and sharing costs and potential benefits of the arrangement. Costs incurred under arrangements where the Company provides research services approximate the amount of revenues recorded. Advance payments for goods or services to be received in the future to be utilized in research and development activities are deferred and capitalized. The capitalized amounts are expensed as the related goods are delivered or the services are rendered.

The Company considers regulatory approval of product candidates to be uncertain, and product manufactured prior to regulatory approval may not be sold unless regulatory approval is obtained. The Company expenses manufacturing costs as incurred to research and development expense for product candidates prior to regulatory approval. If, and when, regulatory approval of a product is obtained, the Company will begin capitalizing manufacturing costs related to the approved product into inventory.

Stock-Based Compensation

The Company measures the cost of equity-based service awards based on the grant-date fair value of the award. The compensation cost is recognized as expense on a straight-line basis over the vesting period for options and restricted stock units (RSUs).

The Company granted performance stock options (“PSO”) to purchase shares of its common stock, which will vest upon the achievement of specified conditions. The Company determined the fair values of these PSOs using the Black-Scholes option pricing model at the date of grant. For the portion of the PSOs for which the performance condition is considered probable, the Company recognizes stock-based compensation expense on the related estimated fair value of such options on a straight-line basis from the date of grant up to the date when it expects the performance condition will be achieved.

The Company adopted the ASU No. 2016-09, Compensation-Stock Compensation Improvements to Employee Share-Based Payment, electing to account for forfeitures as they occur as of January 1, 2017.

The Company accounts for equity instruments issued to non-employees using the fair value approach. These equity instruments consist of stock options and restricted common stock, which are valued using the Black-Scholes option-pricing model. Stock-based compensation expense is recognized as the equity instruments are earned. The measurement of stock-based compensation is subject to periodic adjustments as the underlying equity instruments vest.

The Company utilizes the Black-Scholes option-pricing model for estimating fair value of its stock options and ESPP granted. Option valuation models, including the Black-Scholes option-pricing model, require the input of highly subjective assumptions, and changes in the assumptions used can materially affect the grant-date fair value of an award. These assumptions include the risk-free rate of interest, expected dividend yield, expected volatility and the expected life of the award. For RSUs, the Company bases the fair value of awards on the closing market value of the common stock at the date of grant.

Selling, General and Administrative Expenses

Selling, general and administrative expenses are primarily comprised of compensation and benefits associated with sales and marketing, finance, human resources, legal, information technology and other administrative personnel, outside marketing, advertising and legal expenses and other general and administrative costs. The Company expenses the cost of advertising, including promotional expenses, as incurred. Advertising expenses were $2.8 million, $0, and $0 for the years ended December 31, 2018, 2017 and 2016, respectively.

Income Taxes

The Company uses the liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The Company must then assess the likelihood that the resulting deferred tax assets will be realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. Due to the Company’s lack of earnings history, the net deferred tax assets have been fully offset by a valuation allowance.

The Company recognizes uncertain income tax positions at the largest amount that is more likely than not to be sustained upon audit by the relevant taxing authority. An uncertain income tax position will not be recognized if it has less than a 50% likelihood of being sustained. The Company does not expect its unrecognized tax benefits to change significantly over the next twelve months.

The Company’s policy is to recognize interest and/or penalties related to income tax matters in income tax expense. The Company had accrued no amounts for interest and penalties related to income tax matters in the Company’s consolidated balance sheet at December 31, 2018 and 2017.

Comprehensive Loss

Comprehensive loss is composed of two components: net loss and other comprehensive loss. Other comprehensive loss refers to gains and losses that under U.S. GAAP are recorded as an element of stockholders’ equity, but are excluded from net loss. The Company’s other comprehensive loss included unrealized gains and losses from available-for-sale marketable securities and foreign currency translation adjustments for the years ended December 31, 2018, 2017 and 2016.

Net Loss per Share Attributable to Coherus

Basic net loss per share attributable to Coherus is calculated by dividing the net loss attributable to Coherus by the weighted-average number of shares of common stock outstanding for the period, without consideration for potential dilutive common shares. Since the Company was in a loss position for all periods presented, basic net loss per share attributable to Coherus is the same as diluted net loss per share attributable to Coherus as the inclusion of all potential dilutive common shares would have been anti-dilutive for all periods presented.

The following outstanding dilutive potential shares have been excluded from the calculation of diluted net loss per share attributable to Coherus due to their anti-dilutive effect:

	Year Ended December 31,
	2018		2017		2016
Stock options, including purchases from contributions to ESPP		14,743,547		11,433,069		10,150,136
Restricted stock units		44,387		120,377		—
Shares issuable upon conversion of Convertible Notes		4,473,871		4,473,871		4,473,871
Total		19,261,805		16,027,317		14,624,007

In January 2019, the Company’s board of directors approved a refresh option grant of 2,556,000 shares at an exercise price of $12.37 to the employees and directors.

Recent Accounting Pronouncements

The following are the recent accounting pronouncements adopted by the Company in 2018:

In January 2016, the FASB issued ASU No. 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (ASU 2016-01). ASU 2016-01 makes amendments to the classification and measurement of financial instruments and revises the accounting related to: (1) the classification and measurement of investments in equity securities, and (2) the presentation of certain fair value changes for financial liabilities measured at fair value. In addition, the update also amends certain disclosure requirements associated with the fair value of financial instruments. ASU 2016-01 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2018, and all annual and interim reporting periods thereafter. Early adoptions of certain amendments within the update are permitted. The Company adopted ASU 2016-01 on January 1, 2018 and the adoption did not have a material impact on its consolidated financial statements and related disclosures.

In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments (ASU 2016-15). The amendment to this update addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice. ASU 2016-15 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2018, and all annual and interim reporting periods thereafter. Early adoption is permitted. The Company adopted ASU 2016-15 on January 1, 2018 and the adoption did not have a material effect on its consolidated financial statements and related disclosures.

In October 2016, the FASB issued ASU No. 2016-16, Income Taxes: Intra-Entity Transfers of Assets Other Than Inventory (ASU 2016-16). This update improves the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. ASU 2016-16 amends the guidance to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Consequently, the amendments in this update eliminate the exception for an intra-entity transfer of an asset other than inventory. The amendments in this update do not include new disclosure requirements; however, existing disclosure requirements might be applicable when accounting for the current and deferred income taxes for an intra-entity transfer of an asset other than inventory. ASU 2016-16 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2018, and all annual and interim reporting periods thereafter. Early adoption is permitted. The Company adopted ASU 2016-16 on January 1, 2018 and the adoption did not have a material effect on its consolidated financial statements and related disclosures.

In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash — a consensus of the FASB Emerging Issues Task Force (ASU 2016-18). The purpose of ASU 2016-18 is to provide guidance on the presentation of restricted cash or restricted cash equivalents in the statement of cash flows. Specifically, ASU 2016-18 requires companies to include amounts generally described as restricted cash and restricted cash equivalents in cash and cash equivalents when reconciling beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2018, and all annual and interim periods thereafter. The amendments in ASU 2016-18 should be applied using a retrospective transition method to each period presented. The Company adopted ASU 2016-18 on January 1, 2018 and the adoption did not have a material effect on its consolidated financial statements and related disclosures.

In August 2018, the FASB issued ASU No. 2018-15, Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. (ASU 2018-15). ASU 2018-15 requires a customer in a cloud computing arrangement that is a service contract to follow the internal-use software guidance in Accounting Standards Codification 350-40 to determine which implementation costs to defer and recognize as an asset. ASU 2018-15 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2020, and all annual and interim reporting periods thereafter. Early adoption is permitted. The Company early adopted ASU 2018-15 in the third quarter of 2018 on a prospective basis, and the adoption did not have a material effect on its consolidated financial statements and related disclosures.

The following are the recent accounting pronouncements that the Company has not yet adopted:

In February 2016, the FASB issued ASU No. 2016-02, Leases (ASU 2016-02). ASU 2016-02 aims to make leasing activities more transparent and comparable, and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. ASU 2016-02 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2019, and all annual and interim reporting periods thereafter. Early adoption is permitted. In July 2018, FASB issued additional authoritative guidance, ASU 2018-11, providing companies with an optional prospective transition method. The Company plans to adopt the new standards in the first quarter 2019 using the optional prospective transition method and will recognize a right-of-use asset and lease liability on the adoption date. Based on its lease portfolio as of December 31, 2018, the Company anticipates upon adoption the recognition of lease assets in the range of $6.7 million to $7.7 million, and lease liabilities in the range of $8.7 million to $9.7 million on its consolidated balance sheet, primarily comprised of facility lease agreements for its corporate headquarters and laboratory facilities in California. The Company does not anticipate any material impact to its consolidated statements of operations. The Company will elect the package of practical expedients upon transition, which allows it to apply the guidance prospectively, without reassessing prior conclusions related to contracts containing leases, lease classification and initial direct costs. The Company will also elect an accounting policy that does not recognize right-of-use assets and lease liabilities related to short-term leases. The Company will not elect to apply the hindsight expedient. The Company is in the process of updating its controls and procedures for maintaining and accounting for its lease portfolio under the new guidance.

In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other: Simplifying the Test for Goodwill Impairment (ASU 2017-04), which simplifies the current requirements for testing goodwill for impairment by eliminating the second step of the two-step impairment test to measure the amount of an impairment loss. ASU 2017-04 is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2020, and all annual and interim reporting periods thereafter. Early adoption is permitted. The Company is currently evaluating the impact that the adoption of ASU 2017-04 will have on its consolidated financial statements and related disclosures. The Company has reviewed other recent accounting pronouncements and concluded they are either not applicable to the business or that no material effect is expected on the consolidated financial statements as a result of future adoption.

In June 2018, the FASB issued ASU No. 2018-07, Improvements to Nonemployee Share-Based Payment Accounting (ASU 2018-07), which simplifies the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payment to employees, with certain exceptions. The amendments in ASU 2018-07 are effective for the Company’s interim and annual reporting periods during the year ending December 31, 2019, and all annual and interim reporting periods thereafter. Early adoption is permitted. The Company does not anticipate that the adoption of this ASU will have a material impact on its consolidated financial statements and related disclosures.

In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurements (ASU 2018-13), which eliminates certain disclosure requirements for fair value measurements, and requires public entities to disclose certain new information and modifies some disclosure requirements. The new guidance is effective for the Company’s interim and annual reporting periods during the year ending December 31, 2020, and all annual and interim reporting periods thereafter. Early adoption is permitted. The Company is currently evaluating the impact that the adoption of ASU 2018-13 will have on its consolidated financial statements and related disclosures.

In August 2018, the SEC adopted amendments to certain disclosure requirements in Securities Act Release No. 33-10532, Disclosure Update and Simplification. These amendments eliminate, modify, or integrate into other SEC requirements certain disclosure rules. Among the amendments is the requirement to present an analysis of changes in stockholders’ equity in the interim financial statements included in quarterly reports on Form 10-Q. The analysis, which can be presented as a footnote or separate statement, is required for the current and comparative quarter and year-to-date interim periods. The amendments are effective for all filings made on or after November 5, 2018. In light of the anticipated timing of effectiveness of the amendments and expected proximity of effectiveness to the filing date for most filers’ quarterly reports, the SEC’s Division of Corporate Finance issued a Compliance and Disclosure Interpretation related to Exchange Act Forms, or CDI – Question 105.09, that provides transition guidance related to this disclosure requirement. CDI – Question 105.09 states that the SEC would not object if the filer’s first presentation of the changes in stockholders’ equity is included in its Form 10-Q for the quarter that begins after the effective date of the amendments. As such, the Company adopted these SEC amendments on November 5, 2018 and will present the analysis of changes in stockholders’ equity in its interim financial statements in its March 31, 2019 Form 10-Q. The Company does not anticipate that the adoption of these SEC amendments will have a material effect on the Company’s financial position, results of operations, cash flows or stockholders’ equity.

The Company has reviewed other recent accounting pronouncements and concluded they are either not applicable to the business or that no material effect is expected on the consolidated financial statements as a result of future adoption.

Fair Value Measurements

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

3.	Fair Value Measurements

Financial assets and liabilities are recorded at fair value. The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, restricted cash, investments in marketable securities, accounts receivable, accounts payable and other current liabilities approximate their fair value due to their short maturities. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The accounting guidance describes a fair value hierarchy based on three levels of inputs that may be used to measure fair value, of which the first two are considered observable and the last is considered unobservable. These levels of inputs are the following:

Level 1 — Quoted prices in active markets for identical assets or liabilities.

Level 2 — Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

The Company’s financial instruments consist of Level 1 assets and Level 3 liabilities. Where quoted prices are available in an active market, securities are classified as Level 1. Level 1 assets consist of highly liquid money market funds that are included in cash and cash equivalents, and restricted cash. There were no unrealized gains and losses in the Company’s investments in these money market funds.

In certain cases where there is limited activity or less transparency around inputs to valuation, securities are classified as Level 3. Level 3 liabilities consist of the contingent consideration.

Financial assets and liabilities subject to fair value measurements on a recurring basis and the level of inputs used in such measurements are as follows (in thousands):

	Fair Value Measurements
	December 31, 2018
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds	$	71,062	$	71,062	$	—	$	—
Restricted cash (money market funds)		835		835		—		—
Total financial assets	$	71,897	$	71,897	$	—	$	—
Liabilities:
Contingent consideration	$	60	$	—	$	—	$	60

	Fair Value Measurements
	December 31, 2017
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds	$	125,373	$	125,373	$	—	$	—
Restricted cash (money market funds)		845		845		—		—
Total financial assets	$	126,218	$	126,218	$	—	$	—
Liabilities:
Contingent consideration	$	3,290	$	—	$	—	$	3,290

There were no transfers between Level 1, Level 2 and Level 3 during the periods presented.

Contingent Consideration

As part of the InteKrin acquisition in February 2014, the Company recognized contingent consideration associated with potential payments to be made to the former InteKrin stockholders upon the achievement of certain events specified in the agreements. This fair value measurement is based on significant inputs not observable in the market and thus represents a Level 3 measurement within the fair value hierarchy. The InteKrin purchase agreement provides for contingent consideration to be paid upon (i) the first dosing of a human subject in the first Phase 2 Clinical Trial for CHS-131 ("Earn-Out Payment"), which was achieved and settled by the Company in March 2015, and (ii) per a compound transaction agreement as defined in the purchase agreement (the “Compound Transaction Payment”). The size of the Compound Transaction Payment consideration is tiered based on the size of a license or similar agreement with a third party and the timing of such agreement.

The fair value measurement of the Compound Transaction Payment uses a probability-weighted discounted cash flow approach, and the change in the fair value of the contingent consideration liability is recognized in other income (expense), net within the consolidated statement of operations. The Compound Transaction analysis as of December 31, 2018 applied a 25% risk-adjusted discount rate to measure present value and also captured an additional 8.0% credit spread for counterparty credit risk given the cash payment. Additionally, the Company’s management estimates the probability of occurrence and the timing to formulate an expected cash flow. During 2018, the fair value of the compound transaction payment decreased as a result of reducing estimates of a payout to former InteKrin stockholders. Generally, increases or decreases in the probability of occurrence would result in a directionally similar impact in the fair value measurement of the Compound Transaction Payment and it is estimated that a 1% increase (decrease) in the probability of occurrence would result in an immaterial fair value fluctuation. For the years ended December 31, 2018, 2017 and 2016, the Company recognized a gain of $3.2 million, a gain of $2.3 million and a loss of $4.3 million in other income (expense), net in the consolidated statement of operations, respectively, as a result of the change in the fair value of the Compound Transaction Payment.

The following table sets forth a summary of changes in the estimated fair value of the contingent consideration (in thousands):

Balance as of December 31, 2016	$	5,550
Change in fair value of the contingent consideration liability		(2,260	)
Balance as of December 31, 2017	$	3,290
Change in fair value of the contingent consideration liability		(3,230	)
Balance as of December 31, 2018	$	60

The decrease of $3.2 million in the fair value of the Compound Transaction Payment during the year ended December 31, 2018 was primarily a result of a decrease in the probability of occurrence from 33% to 10% and an extension in the timing of occurrence to a later date.

Convertible Notes

The estimated fair value of the 8.2% Convertible Senior Notes Due 2022, which the Company issued on February 29, 2016 (see Note 7) is based on an income approach. The estimated fair value was approximately $91.1 million (par value $100.0 million) as of December 31, 2018 and represents a Level 3 valuation. When determining the estimated fair value of the Company’s long-term debt, the Company uses a single factor binomial lattice model which incorporates the terms and conditions of the convertible notes and market based risk measurement that are indirectly observable, such as credit risk. The lattice model produces an estimated fair value based on changes in the price of the underlying common shares price over successive periods of time. An estimated yield based on market data is used to discount straight debt cash flows.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Inventory

12 Months Ended

Dec. 31, 2018

Inventory Disclosure [Abstract]

Inventory

The Company began capitalizing inventory in November 2018 once the FDA approved UDENYCA™. Inventory consisted of the following (in thousands):

	December 31,
	2018
Raw materials	$	2,851
Work in process		1,576
Finished goods		1,244
Total	$	5,671

Balance sheet classification (in thousands):

	December 31,
	2018
Inventory	$	1,659
Inventory, non-current		4,012
Total	$	5,671

Inventory expected to be sold in periods more than twelve months from the date presented is classified as inventory, non-current on the balance sheet. As of December 31, 2018, the non-current portion of inventory consisted of raw materials and a portion of work in process.

As of December 31, 2018, prepaid manufacturing on the consolidated balance sheet includes a prepayment of $6.6 million made to a contract manufacturing organization (“CMO”) for manufacturing services which the Company expects to be converted into inventory within the next twelve months.

Balance Sheet Components

12 Months Ended

Dec. 31, 2018

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Balance Sheet Components

5.	Balance Sheet Components

Property and Equipment, Net

Property and equipment, net are as follows (in thousands):

	December 31,			December 31,
	2018			2017
Machinery and equipment	$	11,505		$	15,229
Computer equipment and software		1,651			1,586
Furniture and fixtures		714			714
Leasehold improvements		4,364			4,344
Construction in progress		1,463			702
Total property and equipment		19,697			22,575
Accumulated depreciation and amortization		(13,037	)		(9,802	)
Property and equipment, net	$	6,660		$	12,773

Depreciation and amortization expense was $3.2 million, $3.4 million and $3.0 million for the years ended December 31, 2018, 2017 and 2016, respectively. In the third quarter of 2018, the Company identified an impairment indicator in machinery and equipment and upon further analysis recorded an impairment loss of $3.9 million within research and development expense in the consolidated statement of operations, given the undiscounted future cash flows were less than the carrying amount of the related machinery and equipment. Impairment of property and equipment was $3.9 million and $0.6 million for the years ended December 31, 2018 and 2017, respectively.

Accrued Liabilities

Accrued liabilities are as follows (in thousands):

	December 31,		December 31,
	2018		2017
Accrued clinical - related parties (see Note 13)	$	—	$	510
Accrued clinical and manufacturing		3,950		5,462
Accrued other		3,058		1,004
Accrued liabilities	$	7,008	$	6,976

Collaboration and License Agreement

12 Months Ended

Dec. 31, 2018

Collaboration And License Agreements [Abstract]

Collaborative and License Agreement

6.	Collaboration and License Agreement

The Company recognized revenue related to the collaboration and license agreements for the periods presented as follows (in thousands):

	Year Ended December 31,
	2018		2017		2016
Baxalta	$	—	$	—	$	188,292
Daiichi Sankyo		—		1,556		1,184
Total collaboration and license revenue	$	—	$	1,556	$	189,476

Daiichi Sankyo

In January 2012, the Company entered into a license agreement with Daiichi Sankyo (the “License Agreement”), under which the Company granted certain licenses to Daiichi Sankyo to develop and commercialize biosimilar forms of etanercept and rituximab in Japan, Taiwan, and South Korea with an option to develop in China. Upon execution of the agreement, Daiichi Sankyo paid a non-refundable, upfront license fee of $10.0 million. The agreement had an initial term of ten years.

The Company identified the following deliverables under the agreement: (1) the transfer of intellectual property rights (license), and (2) the manufacture of drug materials for clinical development purposes. The Company considered the provisions of the multiple-element arrangement guidance in determining how to recognize the total consideration of the agreement. The Company concluded that the license was not a separate unit of accounting because Daiichi Sankyo could not benefit from the use of the license rights for their intended purpose without the products manufactured by the Company. Daiichi Sankyo relied upon the Company to manufacture and supply the products necessary for Daiichi Sankyo’s development because the related manufacturing know-how specific to the products is proprietary to the Company and Daiichi Sankyo does not have the right to manufacture the licensed product. The Company determined that neither of the deliverables have standalone value and, therefore, the deliverables were accounted for as a single unit of accounting with the upfront fee recognized as revenue on a straight-line basis over its estimated period of performance of approximately three years, which was regularly evaluated for reasonableness and revised as deemed appropriate on a prospective basis. The Company determined that the straight-line method of revenue recognition was most appropriate for this agreement given there is no discernable pattern of its performance under the arrangement.

In January 2014, the Company and Daiichi Sankyo entered into the Memorandum of Understanding No. 2 (the “MOU 2”) in which both parties agreed to cooperate to conduct a global Phase 3 clinical trial in rheumatoid arthritis. In June 2015, the parties also entered into the Memorandum of Understanding No. 3 (the “MOU 3”) in which both parties agreed to cooperate further on a global Phase 3 clinical trial for an open label, safety extension study (“OLSES”) in rheumatoid arthritis. Daiichi Sankyo was responsible for a minimum of 20% of the cost of the clinical trial. The Company also entered into a clinical supply agreement as part of MOU 2 and MOU 3 in which the Company supplied finished study drug and study comparator drug for Daiichi Sankyo’s use in the Japanese portion of the product’s clinical trial. Daiichi Sankyo reimbursed these research and development costs in quarterly advance payments, and the Company recognized these advance payments as a reduction in the research and development expense when the research and development activity was performed.

In July 2016 and December 2016, the Company entered into three memoranda of understanding (“MOU 4,” “MOU 5” and “MOU 6,” and together with MOU 1, MOU 2 and MOU 3, the “MOUs”) with Daiichi Sankyo. Under MOU 4, MOU 5 and MOU 6, the Company received $4.5 million for reimbursements of certain past costs incurred and the Company recognized these reimbursements as a reduction of research and development expenses when the research and development activity was performed. The Company accounted for the above MOUs as a separate arrangement, which was not deemed to be a material modification of the License Agreement.

In July 2017, Daiichi Sankyo announced its decision, which was accepted by the Company, to discontinue development of the Company’s etanercept (Enbrel) biosimilar product candidate, CHS-0214, in Japan and to conclude the parties’ global open-label safety extension study in rheumatoid arthritis. Pursuant to the License Agreement, the Company regained the rights to develop and commercialize CHS-0214 in Japan. As a result of Daiichi Sankyo’s decision to opt-out of the development of CHS-0214 in Japan and not having any further performance obligations under the license arrangement, the Company recognized the remaining deferred revenue of $1.4 million as a collaboration and license revenue during the second quarter of 2017 in its consolidated statement of operations. As a result, there was no deferred revenue reflected in the consolidated balance sheets as of December 31, 2018 and 2017.

On August 9, 2017, the Company and Daiichi Sankyo entered into a letter of agreement, dated July 29, 2017 to terminate the License Agreement, including, any and all MOUs and other agreements executed between the parties relating to CHS-0214. As a result, the Company did not recognize any MOU cost reimbursement as a reduction of research and development expense in 2018, and recognized $4.2 million and $9.7 million for the years ended December 31, 2017 and 2016, respectively, in its consolidated statements of operations.

Baxalta

The Company entered into a license agreement in August 2013 and two subsequent amendments thereto with Baxalta Incorporated, Baxalta US Inc., and Baxalta GmbH (collectively “Baxalta”) (then Baxter International, Inc., part of Shire plc as of June 2016), to develop and commercialize an etanercept biosimilar molecule, CHS-0214 worldwide, excluding the U.S., Japan, Taiwan, South Korea, China and most of the Caribbean and South American nations (as amended, the “Baxalta Agreement”).

Under the terms of the agreement, the Company was responsible in conducting the development and the regulatory activities, and Baxalta was responsible in conducting the commercialization of the etanercept biosimilar product. In consideration of the exclusive, royalty-bearing license to develop, commercialize and use the etanercept biosimilar product, the Company received an upfront payment and was eligible to receive contingent payments composed of clinical development payments and regulatory milestone payments. If the cumulative development costs exceed the cumulative contingent payments, Baxalta would reimburse the Company for the excess cost as set forth in the agreement up to predetermined limits. Once the etanercept biosimilar product commercializes, the Company was entitled to tiered royalties, based on the manufacturing cost as a percentage of net sales of licensed products, ranging from the mid-single digits to the high teens on a country-by-country basis. These royalties were subject to certain offsets and reductions. The agreement had an initial term of ten years and contained provisions allowing Baxalta to renew the agreement for another three years on a country-by-country basis.

The Company identified the following deliverables under the license agreement with Baxalta: 1) the transfer of intellectual property rights (license), (2) the obligation to provide research and development services including the manufacturing and supply of clinical product, and (3) the obligation to participate on various committees.

The Company considered the provisions of the multiple-element arrangement guidance in determining how to recognize the total consideration of the agreement. The Company determined that the license did not have standalone value to Baxalta without the Company’s technical expertise as it relates to the development of the product candidate and committee participation. Additionally, the license to Baxalta did not include the right to manufacture, or have manufactured the product during the development stage, or to conduct any process development activities. Therefore, the Company concluded that these deliverables represent a single unit of accounting under the multiple-element arrangement guidance.

The upfront payment and clinical development payments included contingent payments that were intended to cover development related expenses incurred by the Company, but potentially reimbursable, in part, to Baxalta under certain limited circumstances. The Company concluded that the contingent payments that contain potentially reimbursable amounts to Baxalta are not substantive milestones under the relevant accounting guidance, since the guidance does not allow the substantive milestone components of a payment to be bifurcated from non-substantive milestone components. The amounts that were contingent payments also contained a claw-back feature that, in the event that the Company commercializes the etanercept biosimilar molecule in the U.S. without Baxalta, the Company would have been required to refund a portion of those contingent payments to Baxalta. Therefore, the Company recorded the portion of the non-substantive contingent payment that contained the claw-back feature as a liability and would have continued to record such liability until the earlier of: (1) expiration of the license agreement pursuant to its terms in August 2023, (2) the earlier termination of the license agreement, or (3) the determination, pursuant to the terms of the license agreement, of the third party to commercialize CHS-0214 in the U.S. These amounts were included in the contingent liability to collaborator on the consolidated balance sheets. The portion of the non-substantive milestone payment that did not contain the claw-back feature were recorded as deferred revenue and recognized as license revenue on a straight-line basis over the remaining estimated performance period of approximately three years, which was regularly evaluated for reasonableness and revised as deemed appropriate on a prospective basis. The Company determined that there was no other method that was more appropriate than the straight-line method of revenue recognition for this agreement given there was no discernable pattern of performance under the arrangement. The Company regularly evaluated the reasonableness of the estimated period of performance and revised the amortization of deferred revenue on a prospective basis, as such, the performance period were extended in September 2014 for two quarters, December 2014 for one quarter, and September 2015 for two months, prior to the termination of the Baxalta Agreement.

The regulatory milestone payments were considered substantive as the achievement was subject to the significant uncertainty as to the outcome of the development efforts, by the Company, over an extended period of time, and the Company’s substantive performance obligation under the license agreement, which included efforts associated with the clinical trials and filing and approval of drug applications by regulatory authorities in various countries. Therefore, the Company recognized revenue associated with these respective contingent payments when each of the specific events were achieved.

On September 26, 2016, Shire issued a termination notice of the Baxalta Agreement, in its entirety as part of its strategic portfolio review after its acquisition of Baxalta. Upon the termination of the Baxalta Agreement, the Company regained from Shire all development and commercial rights previously licensed under the CHS-0214. There were no further contractual obligations and the Company recognized the outstanding balances of deferred revenue of $85.8 million and contingent liability to collaborator of $76.7 million as revenue in its consolidated statements of operations in 2016.

Debt Obligations

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Debt Obligations

7.	Debt Obligations

Convertible Notes

On February 29, 2016, the Company issued and sold $100.0 million aggregate principal amount of its 8.2% Convertible Senior Notes (the “Convertible Notes”) and received total net proceeds of approximately $99.2 million, after deducting issuance costs of $0.8 million. The Convertible Notes constitute general, senior unsubordinated obligations of the Company and are guaranteed by certain subsidiaries of the Company. The Convertible Notes bear interest at a fixed coupon rate of 8.2% per annum payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year, which commenced on March 31, 2016, and mature on March 31, 2022, unless earlier converted, redeemed or repurchased. If the Company fails to satisfy certain registration or reporting requirements, then additional interest will accrue on the Convertible Notes at a rate of up to 0.50% per annum in the aggregate. The Convertible Notes also bear a premium of 9% of their principal amount, which is payable when the Convertible Notes mature or are repurchased or redeemed by the Company.

The Convertible Notes were issued to Healthcare Royalty Partners III, L.P., for $75.0 million in aggregate principal amount, and to three related party investors, KKR Biosimilar L.P., MX II Associates LLC, and KMG Capital Partners, LLC, for $20.0 million, $4.0 million, and $1.0 million, respectively, in aggregate principal amount.

The Convertible Notes are convertible at the option of the holder at any time prior to the close of business on the business day immediately preceding March 31, 2022 at the initial conversion rate of 44.7387 shares of common stock per $1,000 principal amount of Convertible Notes, which is equivalent to an initial conversion price of approximately $22.35 per share, and is subject to adjustment in certain events. Upon conversion of the Convertible Notes by a holder, the holder will receive shares of the Company’s common stock together, if applicable, with cash in lieu of any fractional share.

The Convertible Notes are redeemable in whole, and not in part, at the Company’s option on or after March 31, 2020, if the last reported sale price per share of common stock exceeds 160% of the conversion price on 20 or more trading days during the 30 consecutive trading days preceding the date on which the Company sends notice of such redemption to the holders of the Convertible Notes. At maturity or redemption, if not earlier converted, the Company will pay 109% of the principal amount of the Convertible Notes maturing or being redeemed, together with accrued and unpaid interest, in cash.

The Convertible Notes contain customary events of default (as defined in the Convertible Note purchase agreement), the occurrence of which could result in the acceleration of all amounts due under the Convertible Notes. These events of default include, among others, certain failures to pay amounts due on the Convertible Notes, to deliver the consideration due upon conversion or to settle uninsured judgments, decrees or orders exceeding $10.0 million, and certain defaults on other indebtedness for money borrowed of at least $10.0 million, insolvency-related events and breaches of representations, subject, in some cases, to a cure period. The Convertible Notes also contain covenants restricting the Company’s ability to incur additional indebtedness for borrowed money or convertible preferred stock and to pay dividends or make distributions on the Company’s equity interests, subject to certain exceptions. As of December 31, 2018, the Company was in full compliance with these covenants and there were no events of default under the Convertible Notes.

The Convertible Notes are accounted for in accordance with ASC Subtopic 470-20, Debt with Conversion and Other Options. Pursuant to ASC Subtopic 470-20, the Company evaluated the features embedded in the Convertible Notes and concluded that the embedded features are not required to be bifurcated and accounted for separately from the host debt instrument.

The Company granted the holders of the Convertible Notes certain registration rights requiring the Company to register, under the Securities Act of 1933, as amended, the resale of the shares of common stock issuable upon conversion or settlement of the Convertible Notes.

The following table summarizes information about the components of the Convertible Notes as of December 31, 2018 and 2017 (in thousands):

	December 31,			December 31,
	2018			2017
Principal amount of the Convertible Notes	$	81,750		$	81,750
Unamortized debt discount and debt issuance costs		(4,431	)		(5,544	)
Convertible Notes	$	77,319		$	76,206
Principal amount of the Convertible Notes - related parties	$	27,250		$	27,250
Unamortized debt discount and debt issuance costs - related parties		(1,477	)		(1,848	)
Convertible Notes - related parties	$	25,773		$	25,402
Total Convertible Notes	$	103,092		$	101,608

If the Convertible Notes were converted on December 31, 2018, the holders of the Convertible Notes would receive common shares with an aggregate value of $40.5 million based on the Company’s closing stock price of $9.05.

The following table presents the components of interest expense of the Convertible Notes for the year ended December 31, 2018 and 2017 (in thousands):

	Year Ended December 31,
	2018		2017		2016
Stated coupon interest	$	6,150	$	6,150	$	5,159
Accretion of debt discount and debt issuance costs		1,113		1,014		781
Interest expense	$	7,263	$	7,164	$	5,940
Stated coupon interest - related parties	$	2,050	$	2,050	$	1,720
Accretion of debt discount and debt issuance costs - related parties		371		338		260
Interest expense - related parties	$	2,421	$	2,388	$	1,980
Total interest expense	$	9,684	$	9,552	$	7,920

The remaining unamortized debt discount and debt offering costs related to the Company’s Convertible Notes of approximately $5.9 million as of December 31, 2018, will be amortized using the effective interest rate over the remaining term of the Convertible Notes of 3.25 years. The annual effective interest rate is 9.48% for the Convertible Notes. The Company recognized total interest expense and amortization of the debt discount of $9.7 million and $9.6 million related to the Convertible Notes for the years ended December 31, 2018 and 2017, respectively.

Future payments on the Convertible Notes as of December 31, 2018 are as follows (in thousands):

Year ending December 31,
2019	$	8,200
2020		8,200
2021		8,200
2022		111,050
Total minimum payments		135,650
Less amount representing interest		(26,650	)
Convertible Notes, principal amount		109,000
Less debt discount and debt issuance costs on Convertible Notes		(5,908	)
Net carrying amount of Convertible Notes	$	103,092

Commitments and Contingencies

12 Months Ended

Dec. 31, 2018

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

8.	Commitments and Contingencies

Facility Leases

In July 2015, the Company entered into the office lease space for its corporate headquarters in Redwood City, California under operating lease agreement, which has been subject to an amendment to secure additional space such that the total headquarters lease space is approximately 40,341 square feet. The lease agreement, as amended, provided for aggregate tenant improvement allowance of $1.4 million, which are amortized as a reduction to rent expense on a straight-line basis over the lease term. Additionally, the lease agreement, as amended, provides for certain limited rent abatement and contains annual scheduled rent increases over the lease term. The lease terminates on November 2022 and contains a one-time option to extend the lease term for five years. As part of the lease agreement, the Company obtained a standby letter of credit (the “Letter of Credit”) in an amount of approximately $0.8 million, which may be drawn down by the Landlord to be applied for certain purposes upon the Company’s breach of any provisions under of the lease. The Company will be entitled to periodically reduce the amount of the Letter of Credit during the lease term. The Letter of Credit of $0.8 million is recorded as restricted cash, non-current within the consolidated balance sheet at December 31, 2018 and 2017.

The Company also lease laboratory facilities in Camarillo, California under an operating lease agreement, which has been subject to several amendments necessary to secure additional space and extend the lease term to June 30, 2020, and December 31, 2020 on the two facility structures.

Rent expense is recognized on a straight-line basis over the term of the leases and accordingly, the Company records the difference between cash rent payments and the recognition of rent expense as a deferred rent liability.

Purchase Commitments

The Company entered into agreements for the manufacturing of commercial supply of UDENYCA^TM with a CMO. Under the terms of the agreements, the Company is contractually obligated to make certain payments to the CMO.

The Company enters into contracts in the normal course of business with contract research organizations for preclinical studies and clinical trials and CMO for the manufacture of drug materials. The contracts are cancellable, with varying provisions regarding termination. If a contract with a specific vendor were to be terminated, the Company would only be obligated for products or services that the Company had received as of the effective date of the termination and any applicable cancellation fees.

As of December 31, 2018, the future minimum lease payments under the non-cancellable facility leases and non-cancellable purchase commitment were as follows (in thousands):

Year ending December 31,
2019	$	6,422
2020		27,070
2021		2,672
2022		2,518
Total minimum lease payments	$	38,682

Rent expense was $2.2 million, $2.3 million and $1.7 million for the years ended December 31, 2018, 2017 and 2016, respectively.

Contingencies

On March 3, 2017, Amgen Inc. and Amgen USA Inc. (collectively “Amgen”) filed an action against the Company, KBI Biopharma Inc., the Company’s employee Howard S. Weiser and Does 1-20 in the Superior Court of the State of California, County of Ventura. The complaint alleges that the Company engaged in unfair competition and improperly solicited and hired certain former Amgen employees in order to acquire and access trade secrets and other confidential information belonging to Amgen. On June 1, 2017, Amgen filed a Second Amended Complaint, which alleges as to Coherus (i) unfair competition under California Business and Professions Code Section 17200 et seq., (ii) misappropriation of trade secrets, (iii) aiding and abetting breach of duty of loyalty and (iv) tortious interference with contract. As to defendant Weiser, the Second Amended Complaint alleges (i) unfair competition under California Business and Professions Code Section 17200 et seq., (ii) misappropriation of trade secrets, (iii) breach of contract, (iv) violation of Penal Code Section 502 and (v) breach of duty of loyalty. KBI Biopharma Inc. is not named as a defendant in the Second Amended Complaint. The Second Amended Complaint seeks injunctive relief and monetary damages. Although Amgen has indicated it intends to seek a preliminary injunction, no motion has been filed yet. The court has set a trial date of April 22, 2019.

On May 10, 2017, Amgen Inc. and Amgen Manufacturing Inc. filed an action against the Company in the U.S. District Court for the District of Delaware (the “District Court”) alleging infringement of one or more claims of Amgen’s U.S. patent 8,273,707 (the “‘707 patent”) under 35 U.S.C. § 271. The complaint seeks injunctive relief, monetary damages and attorney fees. On December 7, 2017, the U.S. Magistrate Judge issued under seal a Report and Recommendation to the District Court recommending that the District Court grant, with prejudice, the Company’s pending motion to dismiss Amgen Inc. and Amgen Manufacturing Inc.’s complaint for failure to state a claim pursuant to Federal Rule of Civil Procedure 12(b)(6). On March 26, 2018, Judge Stark of the District Court adopted the U.S. Magistrate Judge’s Report and Recommendation to grant the motion of the Company pursuant to Federal Rule of Civil Procedure 12(b)(6) to dismiss with prejudice the patent infringement complaint alleging infringement of the ‘707 patent on the grounds that such complaint failed to state a claim upon which relief may be granted. In May 2018, Amgen filed a Notice of Appeal in the U.S. Court of Appeals for the Federal Circuit. Amgen and Coherus have filed briefs in this matter and decision on the appeal is expected from the Federal Circuit in 2019.

The Company believes that these lawsuits are without merit and intends to vigorously defend its position. However, if Amgen were to be successful in its effort to seek injunctive relief, these legal actions may negatively affect the Company’s future revenues and results of operations. It is not possible at this time to determine the likelihood of an unfavorable outcome or an estimate of the amount or range of any potential loss.

Guarantees and Indemnifications

In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future, but have not yet been made. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. However, the Company may record charges in the future as a result of these indemnification obligations. The Company would assess the likelihood of any adverse judgments or related claims, as well as ranges of probable losses. In the cases where the Company believes that a reasonably possible or probable loss exists, it will disclose the facts and circumstances of the claims, including an estimate range, if possible.

Stockholders' Equity

12 Months Ended

Dec. 31, 2018

Equity Method Investment Summarized Financial Information Liabilities And Equity [Abstract]

Stockholders' Equity

9.	Stockholders’ Equity

Common Stock Offerings

In January 2016, the Company’s shelf registration statement on Form S-3 (File No. 333-208625) (the “Shelf Registration Statement”) was declared effective by the SEC. As of January 18, 2019, the Company’s Shelf Registration Statement expired.

On October 28, 2016, the Company entered into a sales agreement (the “Sales Agreement”) with Cowen to sell shares of the Company’s common stock, with aggregate gross sales proceeds of up to $100,000,000, from time to time, through an at-the-market equity offering program under which Cowen will act as its sales agent (the “ATM Offering Program”). Cowen is entitled to compensation for its services equal to 3.0% of the gross proceeds of any shares of common stock sold through Cowen under the Sales Agreement. The Company has no obligation to sell any shares under the Sales Agreement, and may at any time suspend solicitation and offers under the Sales Agreement. The shares will be issued pursuant to the Company’s Shelf Registration Statement. The Company filed a prospectus supplement, dated October 28, 2016, with the SEC in connection with the offer and sale of the shares pursuant to the Sales Agreement. In January and December 2017, the Company sold 925,999 shares of common stock at a weighted average price of $12.42 per share through its ATM Offering Program and received total gross proceeds of $11.5 million. After deducting commission of $0.3 million and offering expense of $0.1 million, the net proceeds were $11.1 million. In 2018, the Company issued and sold 1,799,504 shares of common stock at a weighted average price of $12.14 per share through its ATM Offering Program and received total gross proceeds of $21.8 million. After deducting commission of $0.7 million and offering expense of $0.1 million, the net proceeds were $21.0 million. As of December 31, 2018, the Company had $10.1 million remaining under the ATM Offering Program. In January 2019, the Company issued and sold 761,130 shares of common stock at a weighted average price of $11.17 per share through its ATM Program and received total net proceeds of $8.2 million. As of January 18, 2019, the Company’s Shelf Registration Statement expired and accordingly the ATM Offering Program was terminated.

In February and March 2017, the Company issued and sold 5,294,902 shares of common stock at a price of $24.25 per share. The Company received total gross proceeds from the offering of $128.4 million. After deducting underwriting discounts and commissions of $7.7 million and offering expense of $0.3 million, the net proceeds were $120.4 million.

In August 2017, the Company issued and sold an aggregate of 6,556,116 shares of common stock to V-Sciences Investments Pte Ltd, a private limited Singapore company, (“Temasek”) in a private placement transaction at an offering price of $11.4397 per share for gross proceeds of $75.0 million. After deducting offering expenses of $0.1 million, the net proceeds were $74.9 million. Pursuant to the stock purchase agreement, Temasek may purchase additional shares of common stock equal to gross proceeds of $75.0 million, subject to certain conditions. On September 22, 2017, the Company filed a registration statement with the SEC registering the resale of the common stock sold and issued in the private placement transaction as of August 2017, and it was declared effective by the SEC on October 16, 2017.

In December 2017, the Company issued an aggregate of 776,104 shares of common stock to KBI Biopharma, Inc., a contract manufacturing organization (“KBI”), in a private placement transaction at an offering price of $8.7746 per share amounting to $6.8 million. Pursuant to the purchase agreement, as consideration for the issuance of the shares, the Company will not be charged the (i) $4.1 million postponement fee, owed by the Company pursuant to the master service agreement for the postponement of the start of the 2017 manufacturing campaign of UDENYCA™, (ii) $2.7 million campaign reservation fee for the second 2018 manufacturing campaign of UDENYCA™ and (iii) increase of certain batch fees until the 2018 manufacturing campaign of UDENYCA™ begins. The Company provided to KBI the right to receive contingent cash royalty payments, in an amount not to exceed $0.7 million in aggregate, upon the achievement of certain conditions related to the timing of the delivery by KBI to the Company of UDENYCA™. In 2018, KBI was unsuccessful in meeting these conditions, and therefore, the contingent royalty payments expired.

In May 2018, the Company completed an underwritten public offering of 5,948,274 shares of its common stock at a price to the public of $14.50 per shares, which includes the closing of the full exercise of the underwriters’ option to purchase an additional 775,861 shares of common stock. The Company received total gross proceeds from the offering of $86.3 million. After deducting underwriting discounts and commissions of $5.2 million and offering expenses of $0.3 million, the net proceeds were $80.8 million.

Stock Option Plans and Stock-Based Compensation

12 Months Ended

Dec. 31, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock Option Plans and Stock-Based Compensation

10.	Stock Option Plans and Stock-Based Compensation

Equity Incentive Plans

In October 2014, the Company’s board of directors and its stockholders adopted the 2014 Equity Incentive Plan (the “2014 Plan”), which became effective upon the closing of the Company’s IPO on November 6, 2014. The 2014 Plan is subject to automatic annual increases in the number of shares available for issuance on the first business day of each fiscal year equal to four percent (4%) of the number of shares of the Company’s common stock outstanding as of such date or a lesser number of shares as determined by the Company’s board of directors. All remaining shares under the Company’s 2010 Stock Plan (the “2010 Plan”) were transferred to the 2014 Plan upon adoption and any additional shares than would otherwise return to the 2010 Plan as a result of forfeiture, termination or expiration of the awards will return to the 2014 Plan. The 2014 Plan provided for the Company to grant shares and/or options to purchase shares of common stock to employees, directors, consultants and other service providers. As of December 31, 2018, the Company had 388,873 shares of common stock available for future issuance.

In June 2016, the Company adopted the 2016 Employment Commencement Incentive Plan (the “2016 Plan”). The 2016 Plan is designed to comply with the inducement exemption contained in Nasdaq’s Rule 5635(c)(4), which provides for the grant of non-qualified stock options, restricted stock units, restricted stock awards, performance awards, dividend equivalents, deferred stock awards, deferred stock units, stock payment and stock appreciation rights to a person not previously an employee or director of the Company, or following a bona fide period of non-employment, as an inducement material to the individual’s entering into employment with the Company. The Company reserved for future issuance under the 2016 Plan a total of 2,300,000 shares of its common stock for new employees. The 2016 Plan does not provide for any annual increases in the number of shares available. As of December 31, 2018, the Company is authorized to issue 2,300,000 shares of common stock under the 2016 Plan and had 90,750 shares of common stock available for future issuance.

Stock Options

Incentive stock options and non-statutory stock options may be granted with exercise prices of not less than the fair value of the common stock on the date of grant. These stock options were granted to generally vest over four years, expire in ten years from the date of grant and are generally exercisable after vesting.

The following table sets forth the summary of option activities under the 2016 and 2014 Plans:

	Options Outstanding
	Number of Options			Weighted-Average Exercise Price
Balances at December 31, 2017		11,406,219		$	15.321
Granted - at fair value		4,963,100			11.971
Exercised		(477,019	)		4.513
Forfeited /cancelled		(1,217,747	)		19.389
Balances at December 31, 2018		14,674,553		$	14.202

Additional information related to the status of options as of December 31, 2018 is summarized as follows:

	Number of Options		Weighted- Average Exercise Price		Weighted- Average Contractual Terms (Years)		Aggregate Intrinsic Value (in thousands)
Options outstanding		14,674,553	$	14.202		7.23	$	22,368
Options vested and expected to vest		14,674,553	$	14.202		7.23	$	22,368
Options vested and exercisable		8,531,888	$	13.969		6.11	$	22,365

During the years ended December 31, 2018, 2017 and 2016, the total estimated fair value of the options vested was $29.9 million, $29.4 million and $23.2 million, respectively, the estimated weighted-average grant-date fair value of options granted was $7.77, $11.70 and $13.32 per share, respectively, and the aggregate intrinsic value of options exercised was $4.9 million, $2.1 million and $15.8 million, respectively.

The Company recognized stock-based compensation expenses of $31.4 million, $29.0 million and $23.2 million in 2018, 2017 and 2016, respectively, related to employee stock options. As of December 31, 2018, total unrecognized stock-based compensation expenses related to unvested employee stock options was $49.7 million, which is expected to be recognized on a straight-line basis over a weighted-average period of approximately 2.6 years.

Restricted Stock Units

In August 2017, the Compensation Committee of the Company’s board of directors approved the granting of restricted stock units (“RSUs”) to its employees. RSUs are share awards that entitle the holder to receive freely tradable shares of our common stock upon vesting. The RSUs cannot be transferred and are subject to forfeiture if the holder’s employment terminates prior to the release of the vesting restrictions. The Company’s RSUs generally vest from the applicable grant date according to the following vesting schedules: 50% after twelve months, 25% after 18 months, and 25% after 24 months, provided the employee remains continuously employed with the Company. The fair value of RSUs is equal to the closing price of our common stock on the applicable grant date of the RSUs.

The following table sets forth the summary of RSUs activity, under the 2014 Plan:

	RSUs Outstanding
	Number of RSUs			Weighted-Average Grant Date Fair Value
Balances at December 31, 2017		120,377		$	13.975
RSUs granted		5,000			15.600
RSUs vested		(61,804	)		18.622
RSUs cancelled		(19,186	)		12.700
Balances at December 31, 2018		44,387		$	12.700

The total fair value of RSUs vested was $1.0 million during the year ended December 31, 2018 and $2.9 million, which included a $2.7 million bonus payout settled in RSUs, during the year ended December 31, 2017. The total estimated grant date fair value of RSUs was $78,000 during the year ended December 31, 2018 and $6.4 million, which included a $4.3 million bonus payout settled in RSUs during the year ended December 31, 2017. The estimated weighted-average grant-date fair value of RSUs granted was $15.60 per share and $10.43 per share during the years ended December 31, 2018 and 2017, respectively.

The Company recognized stock-based compensation expenses related to RSUs of $0.7 million and $0.6 million for the year ended December 31, 2018 and 2017, respectively. As of December 31, 2018, total unrecognized stock-based compensation expenses related to unvested RSUs was $0.3 million, which is expected to be recognized on a straight-line basis over a weighted-average period of approximately 0.6 years.

Performance Stock Options (“PSOs”)

In April 2018, the Compensation Committee of the Company’s board of directors approved the granting of performance stock option awards to senior officers. PSOs represent a contingent right to purchase the common stock of the Company upon achievement of specified conditions. The PSOs granted will vest upon the achievement of commercial launch and certain sales goals related to UDENYCA^TM. The Company recognized stock-based compensation expense of $0.5 million in 2018 related to PSOs.

Nonemployees Stock-Based Compensation

The Company granted 147,500, 60,000 and 248,650 stock options to purchase shares of common stock to nonemployees during the years ended December 31, 2018, 2017 and 2016, respectively. The weighted-average exercise price of the options granted in 2018, 2017 and 2016 was $14.32, $13.47 and $18.16 per share, respectively. For the years ended December 31, 2018, 2017 and 2016, the Company recorded stock-based compensation expense related to options granted to nonemployees of $1.6 million, $1.9 million and $4.2 million, respectively. The Company remeasures the fair value of the unvested nonemployee options at each period using the Black-Scholes option-pricing model reflecting the same assumptions as applied to employee options in each of the reported years, other than the expected life, which is assumed to be the remaining contractual life of the options.

Employee Stock Purchase Plan

In October 2014, the Company’s board of directors and its stockholders approved the establishment of the 2014 Employee Stock Purchase Plan (“ESPP”). The ESPP provides for annual increases in the number of shares available for issuance on the first business day of each fiscal year, equal to the lesser of one percent (1%) of the number of shares of the Company’s common stock outstanding as of such date, 320,000 shares of common stock, or a number of shares as determined by the Company’s board of directors. The ESPP had 1,923,506 shares of common stock available for future issuance as of December 31, 2018. Eligible employees may purchase common stock at 85% of the lesser of the fair market value of the Company’s common stock on the first or last day of the offering period. The offering periods of ESPP are on May 16 and November 16. The Company recognized stock-based compensation expenses related to ESPP of $0.8 million and $80,000 for the year ended December 31, 2018 and 2017, respectively. As of December 31, 2018, there was $0.7 million of unrecognized compensation expense associated with the ESPP, which is expected to be recognized over an estimated weighted-average period of five months.

Stock-Based Compensation

The stock-based compensation expense is reflected in the consolidated statements of operations as follows (in thousands):

	Year Ended December 31,
	2018		2017		2016
Research and development	$	15,339	$	15,104	$	13,592
General and administrative		19,458		18,293		13,829
	$	34,797	$	33,397	$	27,421

Stock-based compensation of $187,000 was capitalized into inventory for the year ended December 31, 2018. Stock-based compensation capitalized into inventory is recognized as cost of sales when the related product is sold.

The Company has a change of control and involuntary termination benefit agreement in place with the Company’s senior executives. The agreement provided for severance terms, acceleration of options and extension of exercise period in the event of a change of control or involuntary termination. For the year ended December 31, 2017, the Company recorded a non-cash stock-based compensation expense for option modifications of $0.5 million and $1.3 million, which was reflected in research and development and selling, general and administrative expenses in the consolidated statement of operations, respectively. The stock-based compensation expense for the option modifications were primarily due to the Company’s restructuring plan completed in June 2017 (see Note 11).

Valuation Assumptions of Awards Granted to Employees

The Company estimated the fair value of each stock option and awards granted under the ESPP on the date of grant using the Black-Scholes option-pricing model. The following table illustrates the weighted average assumptions for the Black-Scholes option-pricing model used in determining the fair value of the awards during the years ended December 31, 2018, 2017 and 2016:

	Year Ended December 31,
	2018			2017			2016
Expected term (years)
Stock options		6.00			6.00			6.00
ESPP		0.50			0.50			—
Expected volatility
Stock options		71	%		76	%		75	%
ESPP		71	%		68	%		—
Risk-free interest rate
Stock options		2.77	%		2.01	%		1.42	%
ESPP		2.40	%		1.42	%		—
Expected dividend yield
Stock options		0	%		0	%		0	%
ESPP		0	%		0	%		—

Expected Term: The expected term represents the period for which the stock-based awards are expected to be outstanding and is based on the options’ vesting term and contractual term. The Company elected to use the “simplified method” for estimating the expected term, which is calculated as the mid-point between the vesting period and the contractual term of the options.

Expected Volatility: The Company used an average historical stock price volatility of industry peers as representative of future stock price volatility since the Company does not have sufficient trading history for its common stock.

Risk-Free Interest Rate: The Company based the risk-free interest rate by using an equivalent to the expected term based on the U.S. Treasury constant maturity rate as of the date of grant.

Expected Dividends: The Company has not paid and does not anticipate paying any dividends in the near future, and therefore used an expected dividend yield of zero in the valuation model

Restructuring

12 Months Ended

Dec. 31, 2018

Restructuring And Related Activities [Abstract]

Restructuring

11.	Restructuring

On June 21, 2017, the Company commenced and completed a restructuring plan to reduce operating costs to better align its workforce with the needs of its business following the FDA’s June 2017 issuance of a CRL for its BLA for UDENYCA™, in which the FDA stated that it cannot approve the Company’s BLA for UDENYCA™ in its present form and provided recommendations to the Company to address the issues raised in the letter.

In connection with the restructuring, the Company recorded aggregate restructuring charges in its consolidated statement of operations of $3.6 million in June 2017. The restructuring charges included one-time termination fees and other employee-related costs of $1.0 million and $1.1 million in research and development and selling, general and administrative expenses in the consolidated statement of operations, respectively. Additionally, non-cash stock-based compensation expense related to the acceleration of stock options and the extension of post-termination stock option exercise periods of $0.3 million and $1.2 million was reflected in research and development and selling, general and administrative expenses in the consolidated statement of operations, respectively. In the first quarter of 2018, the Company fully settled the $2.1 million of personnel-related restructuring charges, therefore there were no restructuring balances reflected in the Company’s balance sheet as of December 31, 2018.

Income Taxes

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Income Taxes

12.	Income Taxes

The Company utilizes the liability method of accounting for deferred income taxes. Under this method, deferred tax liabilities and assets are recognized for the expected future tax consequences of temporary differences between the carrying amounts and the tax basis of assets and liabilities. A valuation allowance is established against deferred tax assets because, based on the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company’s policy is to record interest and penalties on uncertain tax positions as income tax expense.

The components of loss before income taxes are as follows (in thousands):

	Year Ended December 31,
	2018			2017			2016
Domestic	$	(208,843	)	$	(222,674	)	$	(95,776	)
Foreign		(496	)		(15,496	)		(31,561	)
Total	$	(209,339	)	$	(238,170	)	$	(127,337	)

There was no provision for income taxes for all years presented due to the establishment of a full valuation allowance against the Company’s deferred tax assets.

A reconciliation of the statutory U.S. federal rate to the Company’s effective tax rate is as follows:

	Year Ended December 31,
	2018			2017			2016
Percent of pre-tax income:
U.S. federal statutory income tax rate		21.00	%		34.00	%		34.00	%
State taxes, net of federal benefit		0.16			0.80			1.98
Foreign rate differences		(0.05	)		(2.21	)		(8.43	)
Permanent items		0.15			(0.19	)		(2.02	)
Research and development credit		2.61			2.10			8.38
Effect in NOLs due to adoption of ASU 2016-09		—			4.55			—
U.S. Tax Reform tax rate change		—			(36.90	)		—
Other		2.23			(0.21	)		(0.13	)
Change in valuation allowance		(26.10	)		(1.94	)		(33.78	)
Effective income tax rate		—	%		—	%		—	%

Significant components of the Company’s net deferred tax assets as of December 31, 2018 and 2017 consist of the following (in thousands):

	December 31,
	2018			2017
Net operating loss carryforwards	$	168,753		$	134,420
Research and development credits		39,891			34,435
Depreciation and amortization		7,901			336
Stock-based compensation		17,123			13,119
Other accruals		3,942			655
Gross deferred tax assets		237,610			182,965
In-process research and development		(552	)		(550	)
Gross deferred tax liabilities		(552	)		(550	)
Total net deferred tax asset		237,058			182,415
Less valuation allowance		(237,058	)		(182,415	)
Net deferred tax assets	$	—		$	—

On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (the “Tax Act”) was signed into law. The Tax Act contains several key provisions that may have significant financial statement effects including the remeasurement of deferred taxes and the recognition of liabilities for taxes on mandatory repatriation and certain other foreign income. The Tax Act reduces the corporate tax rate from 35% to 21% effective January 1, 2018. Because ASC 740 requires companies to recognize the effect of tax law changes in the period of enactment, the effects must be recognized by companies’ December 2017 financial statements, even though the effective date for most provisions of the Tax Act was January 1, 2018. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (SAB 118) which allows companies to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. Since the Tax Act was passed late in the fourth quarter of 2017, and ongoing guidance and accounting interpretation was yet to be issued, the accounting of the transition tax and deferred tax re-measurements were incomplete as of December 31, 2017. The Company filed its 2017 Federal corporate income tax return in the fourth quarter of 2018. The final analysis and impact of the Tax Act is reflected in the tax provision and related tax disclosures for the year ended December 31, 2018. There was a gross increase of approximately $2.9 million to the originally estimated $87.9 million remeasurement of deferred tax assets. The $2.9 million remeasurement had no impact on the income statement or balance sheet due to the corresponding valuation allowance offsetting deferred taxes.

The valuation allowance increased $54.6 million, $4.6 million and $43.0 million during the years ended December 31, 2018, 2017 and 2016, respectively.

As of December 31, 2018, the Company had federal net operating loss carryforwards of approximately $783.1 million, which will start to expire beginning in 2031, and various state net operating loss carryforwards of approximately $49.1 million, which have various expiration dates beginning in 2031. Utilization of the net operating loss carryforwards and credits may be subject to a substantial annual limitation due to the ownership change limitations provided by Section 382 of the Internal Revenue Code of 1986, as amended, and similar state provisions. The annual limitation may result in the expiration of net operating losses and credits before utilization. Under the new enacted tax law, the carry forward period of net operating losses generated from 2018 forward is indefinite. However, the carryforward period for net operating losses generated prior to 2018 remains the same. Therefore, the annual limitation may result in the expiration of certain net operating losses and tax credit carryforwards before their utilization.

As of December 31, 2018, the Company had federal research and development credit carryforwards of approximately $44.1 million, which will start to expire in 2031, and state research and development credit carryforwards of approximately $16.2 million, which can be carried forward indefinitely.

In assessing the realizability of deferred tax assets, the Company considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which the temporary differences representing net future deductible amounts become deductible. Due to the Company’s history of losses, and lack of other positive evidence, the Company has determined that it is more likely than not that its net deferred tax assets will not be realized, and therefore, the net deferred tax assets are fully offset by a valuation allowance at December 31, 2018 and 2017. The deferred tax assets were primarily comprised of federal and state tax net operating losses and tax credit carryforwards. Utilization of the net operating loss and tax credit carryforwards may be subject to an annual limitation due to historical or future ownership percentage change rules provided by the Internal Revenue Code of 1986, as amended, and similar state provisions. The annual limitation may result in the expiration of certain net operating loss and tax credit carryforwards before their utilization.

The Company files U.S, California and other state income tax returns with varying statutes of limitations. The tax years from 2011 forward remain open to examination due to the carryover of unused net operating losses and tax credits.

A reconciliation of the Company’s unrecognized tax benefits for the years ended December 31, 2018, 2017 and 2016 is as follows (in thousands):

	Year Ended December 31,
	2018		2017			2016
Balance at beginning of year	$	15,682	$	18,682		$	10,605
Additions based on tax positions related to current year		1,276		3,387			6,111
Additions for tax positions of prior years		1,157		(6,387	)		1,966
Balance at end of year	$	18,115	$	15,682		$	18,682

As of December 31, 2018, 2017 and 2016, the Company had approximately $18.1 million, $15.7 million, and $18.7 million, respectively, of unrecognized benefits, none of which would currently affect the Company’s effective tax rate if recognized due to the Company’s deferred tax assets being fully offset by a valuation allowance. The Company does not believe there will be any material changes in its unrecognized tax positions over the next twelve months. During the years ended December 31, 2018, 2017 and 2016, the Company did not recognize accrued interest and penalties related to unrecognized tax benefits. The Company does not anticipate a material adjustment of unrecognized tax benefits during the next 12 months as reductions for tax positions of prior years.

Related Party Transactions

12 Months Ended

Dec. 31, 2018

Related Party Transactions

13.	Related Party Transactions

Transactions Associated with Medpace Agreement

A prior member of the Company’s board of directors is also the president and chief executive officer of Medpace Inc. (“Medpace”). As such, Medpace was deemed to be a related party until the director’s resignation on March 1, 2018. As a result, the Company no longer reflects balances and transactions associated with Medpace as related party in its consolidated financial statements as of March 1, 2018. As of December 31, 2017, the Company had $0.9 million in prepaid assets (prepaid clinical and other–related parties), $0.2 million in accounts payable–related parties, and $0.5 million in accrued and other liabilities (accrued clinical–related parties), all reflected on the Company’s consolidated balance sheet associated with Medpace. The Company recognized $1.5 million, $8.2 million and $34.6 million during years ended December 31, 2018, 2017 and 2016, respectively, for services rendered by Medpace within research and development expense in the consolidated statements of operations.

Recruiting Services

One member of the Company’s board of directors is a partner of a firm that provides recruiting services to the Company. As such, the recruiting services provided were deemed to be related party transactions. As of December 31, 2018 and 2017, there were no such related party balances in the Company’s consolidated balance sheets. The Company recorded in research and development expense in its consolidated statements of operations, $130,000, $17,000 and $135,000 for the years ended December 31, 2018, 2017 and 2016, respectively, for services rendered by the recruiting company. The Company recorded in selling, general and administrative expense in its consolidated statements of operations, $181,000, $62,000 and $178,000 for the year ended December 31, 2018, 2017 and 2016, respectively, for services rendered by the recruiting company.

Convertible Notes — Related Parties

In February 2016, the Company issued Convertible Notes to certain related parties (some companies affiliated with members of the Company’s board of directors), for an aggregate principal amount of $25.0 million (see Note 7 for related party disclosure).

InteKrin Acquisition

In February 2014, the Company completed the acquisition of the InteKrin for total consideration of $5.0 million. Mr. Dennis M. Lanfear, the chief executive officer of the Company, was the chairman of the board and acting president of InteKrin at the time of the acquisition. As such, the InteKrin acquisition was a related party transaction. Mr. Lanfear also owned 10% of the outstanding securities of InteKrin Russia, a majority owned subsidiary of InteKrin.

In September 2018, InteKrin acquired the outstanding 17.5% of securities of InteKrin Russia held by its non-controlling owners for $0.7 million. As a result of this purchase of the non-controlling ownership in InteKrin Russia, Mr. Lanfear, who was one of the non-controlling stockholders of InteKrin Russia, received $0.4 million in consideration for his shares.

Subsequent Events

12 Months Ended

Dec. 31, 2018

Subsequent Events [Abstract]

Subsequent Events

14.	Subsequent Events

Term Loan

On January 7, 2019 (the “Credit Agreement Closing Date”), the Company entered into a credit agreement (the “Credit Agreement”) with affiliates of Healthcare Royalty Partners (together, the “Lenders”). The Credit Agreement consists of a six-year term loan facility for an aggregate principal amount of $75.0 million (the “Borrowings”). The obligations of the Company under the loan documents are guaranteed by the Company’s material domestic U.S. subsidiaries (the “Guarantors”).

The Borrowings under the Credit Agreement bear interest through maturity at 7.00% per annum plus LIBOR (customarily defined). If the consolidated net sales (customarily defined) for UDENYCA™, the Company’s pegfilgrastim (Neulasta^®) biosimilar, for the fiscal year ending December 31, 2019, are in excess of $250.0 million, then the interest rate will be reduced as of January 1, 2020 to 6.75% per annum plus LIBOR. Interest is payable quarterly in arrears.

Principal payments on the Borrowings are required to be paid in equal quarterly installments beginning on the four year anniversary of the Credit Agreement Closing Date (or, if consolidated net sales of UDENYCA™ in the fiscal year ending December 31, 2021 are less than $375.0 million, beginning on the three year anniversary of the Credit Agreement Closing Date), with the outstanding balance to be repaid on January 7, 2025 (the “Maturity Date”).

The Company is also required to make mandatory prepayments of the Borrowings under the Credit Agreement, subject to specified exceptions, with the proceeds of asset sales, extraordinary receipts, debt issuances and specified other events including the occurrence of a change in control.

If all or any of the Borrowings are prepaid or required to be prepaid under the Credit Agreement, then the Company shall pay, in addition to such prepayment, a prepayment premium (the “Prepayment Premium”) equal to (i) with respect to any prepayment paid or required to be paid on or prior to the three year anniversary of the Credit Agreement Closing Date, 5.00% of the Borrowings prepaid or required to be prepaid, plus all required interest payments that would have been due on the Borrowings prepaid or required to be prepaid through and including the three year anniversary of the Credit Agreement Closing Date, (ii) with respect to any prepayment paid or required to be paid after the three year anniversary of the Credit Agreement Closing Date but on or prior to the four year anniversary of the Credit Agreement Closing Date, 5.00% of the Borrowings prepaid or required to be prepaid, (iii) with respect to any prepayment paid or required to be paid after the four year anniversary of the Credit Agreement Closing Date but on or prior to the five year anniversary of the Credit Agreement Closing Date, 2.50% of the Borrowings prepaid or required to be prepaid, and (iv) with respect to any prepayment paid or required to be prepaid thereafter, 1.25% of the Borrowings prepaid or required to be prepaid.

In connection with the Credit Agreement, the Company paid a fee to the Lenders of $1.1 million at closing in the form of an original issue discount. Upon the prepayment or repayment of the Borrowings (or upon the date such prepayment or repayment is required to be paid), the Company is required to pay an additional exit fee in an amount equal to 4.00% of the total principal amount of the Borrowings.

The obligations under the Credit Agreement are secured by a lien on substantially all of the Company’s and the Guarantors’ tangible and intangible property, including intellectual property. The Credit Agreement contains certain affirmative covenants, negative covenants and events of default, including, covenants and restrictions that among other things, restrict the ability of the Company and its subsidiaries to, incur liens, incur additional indebtedness, make loans and investments, engage in mergers and acquisitions, in asset sales, and declare dividends or redeem or repurchase capital stock. Additionally, the consolidated net sales for UDENYCA™ must not be lower than $70.0 million for the fiscal year ending December 31, 2019, (b) $125.0 million for the fiscal year ending December 31, 2020, and (c) $150.0 million for each fiscal year thereafter. A failure to comply with these covenants could permit the Lenders under the Credit Agreement to declare the Borrowings, together with accrued interest and fees, to be immediately due and payable.

Supplementary Data - Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information

15.	Supplementary Data – Quarterly Financial Data (Unaudited)

The following table presents certain unaudited consolidated quarterly financial information for each of the quarters ended December 31, 2018 and 2017:

	2018 Quarter End
(in thousands, except per share data)	March 31			June 30			September 30			December 31
Total revenue	$	—		$	—		$	—		$	—
Total operating expenses		42,032			44,910			56,972			60,502
Net loss		(44,302	)		(43,685	)		(58,826	)		(62,596	)
Net loss attributable to Coherus		(44,297	)		(43,638	)		(58,808	)		(62,596	)
Net loss per share attributable to Coherus, basic and diluted		(0.74	)		(0.68	)		(0.87	)		(0.92	)

	2017 Quarter End
	March 31			June 30			September 30			December 31
Total revenue	$	161		$	1,395		$	—		$	—
Total operating expenses		72,578			58,033			56,615			46,466
Net loss		(74,822	)		(55,402	)		(58,993	)		(49,069	)
Net loss attributable to Coherus		(74,778	)		(55,336	)		(58,989	)		(49,067	)
Net loss per share attributable to Coherus, basic and diluted		(1.54	)		(1.08	)		(1.09	)		(0.84	)

Basis of Presentation and Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Basis of Consolidation

Use of Estimates

Foreign Currency

Segment Reporting and Customer Concentration

The following table summarizes revenue by geographic region (in thousands):

	Year Ended December 31,
	2018		2017		2016
United States	$	—	$	—	$	188,292
Rest of world		—		1,556		1,814
Total revenue	$	—	$	1,556	$	190,106

Customer Concentration

Customers whose collaboration and license revenue accounted for 10% or more of total revenues were as follows:

	Year Ended December 31,
	2018	2017			2016
Baxalta	N/A	N/A				99	%
Daiichi Sankyo	N/A		100	%	*

*less than 10%

Cash and Cash Equivalents

	December 31,		December 31,
	2018		2017
Cash and cash equivalents	$	72,356	$	126,911
Restricted cash		50		60
Restricted cash - non-current		785		785
Total cash, cash equivalents and restricted cash	$	73,191	$	127,756

Investments in Marketable Securities

Concentration of Credit Risk

Fair Value of Financial Instruments

Inventory

Property and Equipment

Computer equipment and software		3 years
Furniture and fixtures		5 years
Machinery and equipment		5 years
Leasehold improvements		Shorter of lease term or useful life

Impairment of Long Lived Assets and Acquired Intangible Asset

Goodwill

Derivative Liability

Accrued Research and Development Expenses

Accrued Research and Development Expense

Revenue Recognition

Research and Development Expense

Stock-Based Compensation

The Company adopted the ASU No. 2016-09, Compensation-Stock Compensation Improvements to Employee Share-Based Payment, electing to account for forfeitures as they occur as of January 1, 2017.

Selling, General and Administrative Expenses

Income Taxes

Comprehensive Loss

Net Loss per Share Attributable to Coherus

The following outstanding dilutive potential shares have been excluded from the calculation of diluted net loss per share attributable to Coherus due to their anti-dilutive effect:

	Year Ended December 31,
	2018		2017		2016
Stock options, including purchases from contributions to ESPP		14,743,547		11,433,069		10,150,136
Restricted stock units		44,387		120,377		—
Shares issuable upon conversion of Convertible Notes		4,473,871		4,473,871		4,473,871
Total		19,261,805		16,027,317		14,624,007

In January 2019, the Company’s board of directors approved a refresh option grant of 2,556,000 shares at an exercise price of $12.37 to the employees and directors.

Recent Accounting Pronouncements

The following are the recent accounting pronouncements adopted by the Company in 2018:

The following are the recent accounting pronouncements that the Company has not yet adopted:

Fair Value Measurements

Level 1 — Quoted prices in active markets for identical assets or liabilities.

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

In certain cases where there is limited activity or less transparency around inputs to valuation, securities are classified as Level 3. Level 3 liabilities consist of the contingent consideration.

Basis of Presentation and Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Summary of Revenue by Geographical Region

The following table summarizes revenue by geographic region (in thousands):

	Year Ended December 31,
	2018		2017		2016
United States	$	—	$	—	$	188,292
Rest of world		—		1,556		1,814
Total revenue	$	—	$	1,556	$	190,106

Summary of Customers Revenue Accounted for 10% or More of Total Revenue

Customers whose collaboration and license revenue accounted for 10% or more of total revenues were as follows:

	Year Ended December 31,
	2018	2017			2016
Baxalta	N/A	N/A				99	%
Daiichi Sankyo	N/A		100	%	*

*less than 10%

Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash

	December 31,		December 31,
	2018		2017
Cash and cash equivalents	$	72,356	$	126,911
Restricted cash		50		60
Restricted cash - non-current		785		785
Total cash, cash equivalents and restricted cash	$	73,191	$	127,756

Schedule of Estimated Useful Lives of Property Plant and Equipment

Computer equipment and software		3 years
Furniture and fixtures		5 years
Machinery and equipment		5 years
Leasehold improvements		Shorter of lease term or useful life

Outstanding Dilutive Potential Shares Excluded from Calculation of Diluted Net Loss Per Share Attributable to Coherus

The following outstanding dilutive potential shares have been excluded from the calculation of diluted net loss per share attributable to Coherus due to their anti-dilutive effect:

	Year Ended December 31,
	2018		2017		2016
Stock options, including purchases from contributions to ESPP		14,743,547		11,433,069		10,150,136
Restricted stock units		44,387		120,377		—
Shares issuable upon conversion of Convertible Notes		4,473,871		4,473,871		4,473,871
Total		19,261,805		16,027,317		14,624,007

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Measured on a Recurring Basis

Financial assets and liabilities subject to fair value measurements on a recurring basis and the level of inputs used in such measurements are as follows (in thousands):

	Fair Value Measurements
	December 31, 2018
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds	$	71,062	$	71,062	$	—	$	—
Restricted cash (money market funds)		835		835		—		—
Total financial assets	$	71,897	$	71,897	$	—	$	—
Liabilities:
Contingent consideration	$	60	$	—	$	—	$	60

	Fair Value Measurements
	December 31, 2017
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds	$	125,373	$	125,373	$	—	$	—
Restricted cash (money market funds)		845		845		—		—
Total financial assets	$	126,218	$	126,218	$	—	$	—
Liabilities:
Contingent consideration	$	3,290	$	—	$	—	$	3,290

Summary of Changes in the Estimated Fair Value of Contingent Consideration

The following table sets forth a summary of changes in the estimated fair value of the contingent consideration (in thousands):

Balance as of December 31, 2016	$	5,550
Change in fair value of the contingent consideration liability		(2,260	)
Balance as of December 31, 2017	$	3,290
Change in fair value of the contingent consideration liability		(3,230	)
Balance as of December 31, 2018	$	60

Inventory (Tables)

12 Months Ended

Dec. 31, 2018

Inventory Disclosure [Abstract]

Schedule of Inventory

The Company began capitalizing inventory in November 2018 once the FDA approved UDENYCA™. Inventory consisted of the following (in thousands):

	December 31,
	2018
Raw materials	$	2,851
Work in process		1,576
Finished goods		1,244
Total	$	5,671

Schedule of Balance Sheet Classification

Balance sheet classification (in thousands):

	December 31,
	2018
Inventory	$	1,659
Inventory, non-current		4,012
Total	$	5,671

Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2018

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Schedule of Property and Equipment, Net

Property and equipment, net are as follows (in thousands):

	December 31,			December 31,
	2018			2017
Machinery and equipment	$	11,505		$	15,229
Computer equipment and software		1,651			1,586
Furniture and fixtures		714			714
Leasehold improvements		4,364			4,344
Construction in progress		1,463			702
Total property and equipment		19,697			22,575
Accumulated depreciation and amortization		(13,037	)		(9,802	)
Property and equipment, net	$	6,660		$	12,773

Schedule of Accrued Liabilities

Accrued Liabilities

Accrued liabilities are as follows (in thousands):

	December 31,		December 31,
	2018		2017
Accrued clinical - related parties (see Note 13)	$	—	$	510
Accrued clinical and manufacturing		3,950		5,462
Accrued other		3,058		1,004
Accrued liabilities	$	7,008	$	6,976

Collaboration and License Agreement (Tables)

12 Months Ended

Dec. 31, 2018

Collaboration And License Agreements [Abstract]

Schedule of Revenue Related to Collaboration and License Agreements

The Company recognized revenue related to the collaboration and license agreements for the periods presented as follows (in thousands):

	Year Ended December 31,
	2018		2017		2016
Baxalta	$	—	$	—	$	188,292
Daiichi Sankyo		—		1,556		1,184
Total collaboration and license revenue	$	—	$	1,556	$	189,476

Debt Obligations (Tables)

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Components of Convertible Notes

The following table summarizes information about the components of the Convertible Notes as of December 31, 2018 and 2017 (in thousands):

	December 31,			December 31,
	2018			2017
Principal amount of the Convertible Notes	$	81,750		$	81,750
Unamortized debt discount and debt issuance costs		(4,431	)		(5,544	)
Convertible Notes	$	77,319		$	76,206
Principal amount of the Convertible Notes - related parties	$	27,250		$	27,250
Unamortized debt discount and debt issuance costs - related parties		(1,477	)		(1,848	)
Convertible Notes - related parties	$	25,773		$	25,402
Total Convertible Notes	$	103,092		$	101,608

Components of Interest Expense of Convertible Notes

The following table presents the components of interest expense of the Convertible Notes for the year ended December 31, 2018 and 2017 (in thousands):

	Year Ended December 31,
	2018		2017		2016
Stated coupon interest	$	6,150	$	6,150	$	5,159
Accretion of debt discount and debt issuance costs		1,113		1,014		781
Interest expense	$	7,263	$	7,164	$	5,940
Stated coupon interest - related parties	$	2,050	$	2,050	$	1,720
Accretion of debt discount and debt issuance costs - related parties		371		338		260
Interest expense - related parties	$	2,421	$	2,388	$	1,980
Total interest expense	$	9,684	$	9,552	$	7,920

Schedule of Future Payments on the Convertible Notes

Future payments on the Convertible Notes as of December 31, 2018 are as follows (in thousands):

Year ending December 31,
2019	$	8,200
2020		8,200
2021		8,200
2022		111,050
Total minimum payments		135,650
Less amount representing interest		(26,650	)
Convertible Notes, principal amount		109,000
Less debt discount and debt issuance costs on Convertible Notes		(5,908	)
Net carrying amount of Convertible Notes	$	103,092

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2018

Commitments And Contingencies Disclosure [Abstract]

Schedule of Future Minimum Lease Payments Under Non-Cancellable Facility Leases and Non- Cancellable Purchase Commitment

As of December 31, 2018, the future minimum lease payments under the non-cancellable facility leases and non-cancellable purchase commitment were as follows (in thousands):

Year ending December 31,
2019	$	6,422
2020		27,070
2021		2,672
2022		2,518
Total minimum lease payments	$	38,682

Stock Option Plans and Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Option Activities under 2016 and 2014 Plans

The following table sets forth the summary of option activities under the 2016 and 2014 Plans:

	Options Outstanding
	Number of Options			Weighted-Average Exercise Price
Balances at December 31, 2017		11,406,219		$	15.321
Granted - at fair value		4,963,100			11.971
Exercised		(477,019	)		4.513
Forfeited /cancelled		(1,217,747	)		19.389
Balances at December 31, 2018		14,674,553		$	14.202

Summary of Additional Information Related to Status of Options

Additional information related to the status of options as of December 31, 2018 is summarized as follows:

	Number of Options		Weighted- Average Exercise Price		Weighted- Average Contractual Terms (Years)		Aggregate Intrinsic Value (in thousands)
Options outstanding		14,674,553	$	14.202		7.23	$	22,368
Options vested and expected to vest		14,674,553	$	14.202		7.23	$	22,368
Options vested and exercisable		8,531,888	$	13.969		6.11	$	22,365

Summary of RSU Activity, under 2014 Plan

The following table sets forth the summary of RSUs activity, under the 2014 Plan:

	RSUs Outstanding
	Number of RSUs			Weighted-Average Grant Date Fair Value
Balances at December 31, 2017		120,377		$	13.975
RSUs granted		5,000			15.600
RSUs vested		(61,804	)		18.622
RSUs cancelled		(19,186	)		12.700
Balances at December 31, 2018		44,387		$	12.700

Schedule of Stock-Based Compensation Expense

The stock-based compensation expense is reflected in the consolidated statements of operations as follows (in thousands):

	Year Ended December 31,
	2018		2017		2016
Research and development	$	15,339	$	15,104	$	13,592
General and administrative		19,458		18,293		13,829
	$	34,797	$	33,397	$	27,421

Schedule of Weighted Average Assumptions for Black-Scholes Option-Pricing Model Used in Determining Fair Value of Awards

The following table illustrates the weighted average assumptions for the Black-Scholes option-pricing model used in determining the fair value of the awards during the years ended December 31, 2018, 2017 and 2016:

	Year Ended December 31,
	2018			2017			2016
Expected term (years)
Stock options		6.00			6.00			6.00
ESPP		0.50			0.50			—
Expected volatility
Stock options		71	%		76	%		75	%
ESPP		71	%		68	%		—
Risk-free interest rate
Stock options		2.77	%		2.01	%		1.42	%
ESPP		2.40	%		1.42	%		—
Expected dividend yield
Stock options		0	%		0	%		0	%
ESPP		0	%		0	%		—

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Components of Loss Before Income Taxes

The components of loss before income taxes are as follows (in thousands):

	Year Ended December 31,
	2018			2017			2016
Domestic	$	(208,843	)	$	(222,674	)	$	(95,776	)
Foreign		(496	)		(15,496	)		(31,561	)
Total	$	(209,339	)	$	(238,170	)	$	(127,337	)

Reconciliation of Statutory U.S. Federal Rate

A reconciliation of the statutory U.S. federal rate to the Company’s effective tax rate is as follows:

	Year Ended December 31,
	2018			2017			2016
Percent of pre-tax income:
U.S. federal statutory income tax rate		21.00	%		34.00	%		34.00	%
State taxes, net of federal benefit		0.16			0.80			1.98
Foreign rate differences		(0.05	)		(2.21	)		(8.43	)
Permanent items		0.15			(0.19	)		(2.02	)
Research and development credit		2.61			2.10			8.38
Effect in NOLs due to adoption of ASU 2016-09		—			4.55			—
U.S. Tax Reform tax rate change		—			(36.90	)		—
Other		2.23			(0.21	)		(0.13	)
Change in valuation allowance		(26.10	)		(1.94	)		(33.78	)
Effective income tax rate		—	%		—	%		—	%

Components of Net Deferred Tax Assets

Significant components of the Company’s net deferred tax assets as of December 31, 2018 and 2017 consist of the following (in thousands):

	December 31,
	2018			2017
Net operating loss carryforwards	$	168,753		$	134,420
Research and development credits		39,891			34,435
Depreciation and amortization		7,901			336
Stock-based compensation		17,123			13,119
Other accruals		3,942			655
Gross deferred tax assets		237,610			182,965
In-process research and development		(552	)		(550	)
Gross deferred tax liabilities		(552	)		(550	)
Total net deferred tax asset		237,058			182,415
Less valuation allowance		(237,058	)		(182,415	)
Net deferred tax assets	$	—		$	—

Reconciliation of Unrecognized Tax Benefits

A reconciliation of the Company’s unrecognized tax benefits for the years ended December 31, 2018, 2017 and 2016 is as follows (in thousands):

	Year Ended December 31,
	2018		2017			2016
Balance at beginning of year	$	15,682	$	18,682		$	10,605
Additions based on tax positions related to current year		1,276		3,387			6,111
Additions for tax positions of prior years		1,157		(6,387	)		1,966
Balance at end of year	$	18,115	$	15,682		$	18,682

Supplementary Data - Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information

The following table presents certain unaudited consolidated quarterly financial information for each of the quarters ended December 31, 2018 and 2017:

	2018 Quarter End
(in thousands, except per share data)	March 31			June 30			September 30			December 31
Total revenue	$	—		$	—		$	—		$	—
Total operating expenses		42,032			44,910			56,972			60,502
Net loss		(44,302	)		(43,685	)		(58,826	)		(62,596	)
Net loss attributable to Coherus		(44,297	)		(43,638	)		(58,808	)		(62,596	)
Net loss per share attributable to Coherus, basic and diluted		(0.74	)		(0.68	)		(0.87	)		(0.92	)

	2017 Quarter End
	March 31			June 30			September 30			December 31
Total revenue	$	161		$	1,395		$	—		$	—
Total operating expenses		72,578			58,033			56,615			46,466
Net loss		(74,822	)		(55,402	)		(58,993	)		(49,069	)
Net loss attributable to Coherus		(74,778	)		(55,336	)		(58,989	)		(49,067	)
Net loss per share attributable to Coherus, basic and diluted		(1.54	)		(1.08	)		(1.09	)		(0.84	)

Organization and Operations - Additional Information (Details) - USD ($)		1 Months Ended		2 Months Ended	12 Months Ended
	Jan. 07, 2019	Jan. 31, 2019	May 31, 2018	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Organization And Operations [Line Items]
Accumulated deficit					$ 984,831,000	$ 775,492,000
Cash and cash equivalents					$ 72,356,000	$ 126,911,000
At-the-Market Equity Offering Program
Organization And Operations [Line Items]
Common stock, shares issued and sold				5,294,902	1,799,504
Share price				$ 24.25
Common stock, net proceeds				$ 120,400,000	$ 21,000,000
At-the-Market Equity Offering Program \| Weighted Average
Organization And Operations [Line Items]
Share price					$ 12.14
Underwritten Public Offering
Organization And Operations [Line Items]
Common stock, shares issued and sold			5,948,274
Common stock, net proceeds			$ 80,800,000
Sale of price per share			$ 14.50
Underwriters’ Option to Purchase Additional Shares
Organization And Operations [Line Items]
Common stock, shares issued and sold			775,861
Subsequent Event \| HRP III Member \| Credit Agreement
Organization And Operations [Line Items]
Term loan facility term	6 years
Line of credit facility, maximum borrowing capacity	$ 75,000,000
Cash and cash equivalents, proceeds from credit agreement		$ 73,100,000

Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details)	1 Months Ended		12 Months Ended
	Jan. 31, 2019 $ / shares shares	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) Segments shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Payments to acquire securities of non-controlling interest in subsidiary			$ 300,000
Foreign exchange gain (loss)			$ (571,000)	$ 52,000	$ (53,000)
Number of reportable segment \| Segments			1
Number of operating segments \| Segments			1
Impairment of property and equipment			$ 3,900,000	600,000
Advertising expenses			$ 2,800,000	0	0
Income tax examination, description			less than a 50%
Unrecognized tax benefits, interest and penalties accrued related to income tax matters			$ 0	0
Share based payment options grants \| shares			4,963,100
Minimum \| ASU No. 2016-02, Leases
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Operating lease, right-of-use asset			$ 6,700
Operating lease, liability			8,700
Maximum \| ASU No. 2016-02, Leases
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Operating lease, right-of-use asset			7,700
Operating lease, liability			9,700
Subsequent Event \| Employees and Directors
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Share based payment options grants \| shares	2,556,000
Share-based payment options exercise price \| $ / shares	$ 12.37
InteKrin Therapeutics Inc
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Impairment of property and equipment			3,900,000	558,000	$ 0
Impairment of goodwill			0
InteKrin Therapeutics Inc \| In Process Research and Development
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Impairment of intangible assets excluding goodwill			0
Available-for-Sale Securities \| Investment in Marketable Securities
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Interest income from marketable securities			$ 1,400,000	$ 800,000
RUSSIA \| Coherus Intermediate Corp, InteKrin Therapeutics, Inc.
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of securities acquired		17.50%
Payments to acquire securities of non-controlling interest in subsidiary		$ 700,000

Basis of Presentation and Summary of Significant Accounting Policies - Summary of Revenue by Geographical Region (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenue	$ 0	$ 1,556	$ 190,106
United States
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenue	0	0	188,292
Rest of World
Revenues From External Customers And Long Lived Assets [Line Items]
Total revenue	$ 0	$ 1,556	$ 1,814

Basis of Presentation and Summary of Significant Accounting Policies - Summary of Customers Revenue Accounted for 10% or More of Total Revenue (Details) - Collaboration and License Revenue - Customer Concentration Risk

12 Months Ended

Dec. 31, 2018

^[1]

Dec. 31, 2017

Dec. 31, 2016

Baxalta

Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]

Percentage of total revenues by single customer

^[1]

99.00%

Daiichi Sankyo

Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]

Percentage of total revenues by single customer

100.00%

^[1]

[1]	less than 10%

Basis of Presentation and Summary of Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Cash and cash equivalents	$ 72,356	$ 126,911
Restricted cash	50	60
Restricted cash, non-current	785	785
Total cash, cash equivalents and restricted cash	$ 73,191	$ 127,756	$ 125,792	$ 159,071

Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Property Plant and Equipment (Details)	12 Months Ended
	Dec. 31, 2018
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Estimated useful lives	3 years
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Estimated useful lives	5 years
Machinery and Equipment
Property Plant And Equipment [Line Items]
Estimated useful lives	5 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Estimated useful lives, description	Shorter of lease term or useful life

Basis of Presentation and Summary of Significant Accounting Policies - Outstanding Dilutive Potential Shares Excluded from Calculation of Diluted Net Loss Per Share Attributable to Coherus (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from the calculation of diluted net loss per share	19,261,805	16,027,317	14,624,007
Stock Options, Including Purchases from Contributions to ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from the calculation of diluted net loss per share	14,743,547	11,433,069	10,150,136
Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from the calculation of diluted net loss per share	44,387	120,377	0
Shares Issuable Upon Conversion of Convertible Notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from the calculation of diluted net loss per share	4,473,871	4,473,871	4,473,871

Fair Value Measurements - Additional Information (Details)		12 Months Ended
	Feb. 29, 2016 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Fair Value Disclosures [Line Items]
Transfers from Level 1 to Level 3		$ 0	$ 0
Transfers from Level 3 to Level 1		0	0
Remeasurement of fair-value contingent consideration		(3,230,000)	(2,260,000)	$ 4,305,000
8.2% Senior Convertible Notes Due 2022
Fair Value Disclosures [Line Items]
Aggregate principal amount	$ 100,000,000
Convertible notes, interest rate	8.20%
Debt instrument maturity date	Mar. 31, 2022
Other Expense, Net
Fair Value Disclosures [Line Items]
Remeasurement of fair-value contingent consideration		3,200,000	2,300,000	$ (4,300,000)
Contingent Consideration
Fair Value Disclosures [Line Items]
Decrease in fair value of the compound transaction payment		(3,230,000)	$ (2,260,000)
Level 3 \| 8.2% Senior Convertible Notes Due 2022
Fair Value Disclosures [Line Items]
Debt instrument fair value		$ 91,100,000
Fair Value Measurements Recurring Basis \| Level 3 \| Contingent Consideration
Fair Value Disclosures [Line Items]
Increase (decrease) in expected probability of compound transaction payment occurrence		1.00%
Expected probability of compound transaction payment occurrence		10.00%	33.00%
Fair Value Measurements Recurring Basis \| Level 3 \| Contingent Consideration \| Measurement Input, Discount Rate
Fair Value Disclosures [Line Items]
Fair value investment measurement input		25
Fair Value Measurements Recurring Basis \| Level 3 \| Contingent Consideration \| Measurement Input, Counterparty Credit Risk
Fair Value Disclosures [Line Items]
Fair value investment measurement input		8.0
Fair Value Measurements Recurring Basis \| Money Market Funds \| Level 1
Fair Value Disclosures [Line Items]
Unrealized gains and losses on investments		$ 0

Fair Value Measurements - Financial Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value Measurements Recurring Basis - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial assets	$ 71,897	$ 126,218
Contingent Consideration
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial liabilities	60	3,290
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial assets	71,897	126,218
Level 3 \| Contingent Consideration
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial liabilities	60	3,290
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial assets	71,062	125,373
Money Market Funds \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial assets	71,062	125,373
Restricted Cash (Money Market Funds)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial assets	835	845
Restricted Cash (Money Market Funds) \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total financial assets	$ 835	$ 845

Fair Value Measurements - Summary of Changes in the Estimated Fair Value of Contingent Consideration (Details) - Contingent Consideration - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 3,290	$ 5,550
Change in fair value of the contingent consideration liability	(3,230)	(2,260)
Ending balance	$ 60	$ 3,290

Inventory - Schedule of Inventory (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Inventory Disclosure [Abstract]
Raw materials	$ 2,851
Work in process	1,576
Finished goods	1,244
Total	$ 5,671

Inventory - Schedule of Balance Sheet Classification (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Inventory Disclosure [Abstract]
Inventory	$ 1,659
Inventory, non-current	4,012
Total	$ 5,671

Inventory - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Inventory [Line Items]
Prepayment made for manufacturing services	$ 7,906	$ 14,969
Contract Manufacturing Organization
Inventory [Line Items]
Prepayment made for manufacturing services	$ 6,600

Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Total property and equipment	$ 19,697	$ 22,575
Accumulated depreciation and amortization	(13,037)	(9,802)
Property and equipment, net	6,660	12,773
Machinery and Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	11,505	15,229
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Total property and equipment	1,651	1,586
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Total property and equipment	714	714
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	4,364	4,344
Construction in Progress
Property Plant And Equipment [Line Items]
Total property and equipment	$ 1,463	$ 702

Balance Sheet Components - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Line Items]
Depreciation and amortization		$ 3,235	$ 3,398	$ 2,996
Impairment of property and equipment		$ 3,900	$ 600
Machinery and Equipment \| Research and Development Expense
Property Plant And Equipment [Line Items]
Impairment of property and equipment	$ 3,900

Balance Sheet Components - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Accrued clinical - related parties	$ 0	$ 510
Accrued clinical and manufacturing	3,950	5,462
Accrued other	3,058	1,004
Accrued liabilities	$ 7,008	$ 6,976

Collaboration and License Agreements - Schedule of Revenue Related to Collaboration and License Agreements (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and license revenue	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 1,395	$ 161	$ 0	$ 1,556	$ 189,476
Baxalta License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and license revenue									0	0	188,292
Daiichi Sankyo License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and license revenue									$ 0	$ 1,556	$ 1,184

Collaboration and License Agreement - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended								12 Months Ended
	Jun. 30, 2015	Jan. 31, 2012	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration and license revenue			$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 1,395,000	$ 161,000	$ 0	$ 1,556,000	$ 189,476,000
Daiichi Sankyo License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue		$ 10,000,000	$ 0				$ 0				$ 0	0
Initial term of agreement		10 years
Renewal term of agreement		3 years
Estimated period of performance upfront fee											3 years
Minimum percentage of clinical trial cost	20.00%
Reimbursement of past cost incurred and to be incurred													4,500,000
Collaboration and license revenue											$ 0	1,556,000	1,184,000
Research and development												4,200,000	9,700,000
Baxalta License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Initial term of agreement											10 years
Renewal term of agreement											3 years
Collaboration and license revenue											$ 0	$ 0	188,292,000
Business acquisition date											Jun. 03, 2016
Expiration of license agreement											2023-08
Deferred revenue recognized													85,800,000
Collaboration Agreement Contingent Liability Noncurrent Recognized													76,700,000
Contractual obligations													$ 0

Debt Obligations - Additional Information (Details)		12 Months Ended
Debt Obligations - Additional Information (Details)	Feb. 29, 2016 USD ($) d $ / shares shares	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of convertible notes				$ 75,000,000
KKR Member
Debt Instrument [Line Items]
Aggregate principal amount	$ 20,000,000
MX II Member
Debt Instrument [Line Items]
Aggregate principal amount	4,000,000
KMGCP Member
Debt Instrument [Line Items]
Aggregate principal amount	1,000,000
HRP III Member
Debt Instrument [Line Items]
Aggregate principal amount	75,000,000
8.2% Senior Convertible Notes Due 2022
Debt Instrument [Line Items]
Aggregate principal amount	$ 100,000,000
Convertible notes, interest rate	8.20%
Proceeds from issuance of convertible notes	$ 99,200,000
Convertible notes, Issuance Cost	$ 800,000
Convertible notes, interest rate description		The Convertible Notes bear interest at a fixed coupon rate of 8.2% per annum payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year, which commenced on March 31, 2016
Debt instrument maturity date	Mar. 31, 2022
Convertible notes, premium percentage	9.00%
Common shares at conversion \| shares	44.7387
Conversion price per common share \| $ / shares	$ 22.35
Principal amount of notes converted into shares	$ 1,000
Percentage of applicable conversion price	160.00%
Convertible trading days \| d	20
Convertible consecutive trading days \| d	30
Percentage to pay in cash of the par value of notes	109.00%
Minimum order amount to be settled		$ 10,000,000
Minimum borrowings for indebtedness defaulters		$ 10,000,000
Convertible notes, covenant compliance		As of December 31, 2018, the Company was in full compliance with these covenants and there were no events of default under the Convertible Notes.
Convertible notes, converted amount		$ 40,500,000
Closing stock, price per share \| $ / shares		$ 9.05
Unamortized debt discount and debt issuance costs on Convertible Notes		$ 5,908,000
Amortized effective interest rate convertible notes period		3 years 3 months
Convertible notes, effective interest rate		9.48%
Total interest expense related to accrued interest and amortization of debt discount		$ 9,700,000	$ 9,600,000
8.2% Senior Convertible Notes Due 2022 \| Maximum
Debt Instrument [Line Items]
Additional interest to be accrued upon failure of registration or reporting requirements	0.50%

Debt Obligations - Components of Convertible Notes (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Feb. 29, 2016
Debt Instrument [Line Items]
Convertible Notes	$ 77,319,000	$ 76,206,000
Convertible Notes - related parties	25,773,000	25,402,000
8.2% Senior Convertible Notes Due 2022
Debt Instrument [Line Items]
Principal amount of the Convertible Notes			$ 100,000,000
Unamortized debt discount and debt issuance costs	(5,908,000)
Total Convertible Notes	103,092,000	101,608,000
8.2% Senior Convertible Notes Due 2022 \| Related Party Debt
Debt Instrument [Line Items]
Principal amount of the Convertible Notes	27,250,000	27,250,000
Unamortized debt discount and debt issuance costs	(1,477,000)	(1,848,000)
Convertible Notes - related parties	25,773,000	25,402,000
8.2% Senior Convertible Notes Due 2022 \| Parent Company
Debt Instrument [Line Items]
Principal amount of the Convertible Notes	81,750,000	81,750,000
Unamortized debt discount and debt issuance costs	(4,431,000)	(5,544,000)
Convertible Notes	$ 77,319,000	$ 76,206,000

Debt Obligations - Components of Interest Expense of Convertible Notes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Accretion of debt discount and debt issuance costs	$ 1,484	$ 1,352	$ 1,041
Interest expense	2,421	2,388	1,980
Total interest expense	9,684	9,552	7,980
8.2% Senior Convertible Notes Due 2022
Debt Instrument [Line Items]
Interest expense	9,700	9,600
Total interest expense	9,684	9,552	7,920
8.2% Senior Convertible Notes Due 2022 \| Related Party Debt
Debt Instrument [Line Items]
Stated coupon interest	2,050	2,050	1,720
Accretion of debt discount and debt issuance costs	371	338	260
Interest expense	2,421	2,388	1,980
8.2% Senior Convertible Notes Due 2022 \| Parent Company
Debt Instrument [Line Items]
Stated coupon interest	6,150	6,150	5,159
Accretion of debt discount and debt issuance costs	1,113	1,014	781
Interest expense	$ 7,263	$ 7,164	$ 5,940

Debt Obligations - Schedule of Future Payments on the Convertible Notes (Details) - 8.2% Senior Convertible Notes Due 2022 $ in Thousands	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
2019	$ 8,200
2020	8,200
2021	8,200
2022	111,050
Total minimum payments	135,650
Less amount representing interest	(26,650)
Convertible Notes, principal amount	109,000
Less debt discount and debt issuance costs on Convertible Notes	(5,908)
Net carrying amount of Convertible Notes	$ 103,092

Commitments and Contingencies - Additional Information (Details) $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2015 USD ($) ft²	Dec. 31, 2018 USD ($) Facility	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Purchase Commitment Excluding Longterm Commitment [Line Items]
Area of office space leased \| ft²	40,341
Number of laboratory facility structure \| Facility		2
Rent expense		$ 2.2	$ 2.3	$ 1.7
Corporate Headquarters Lease
Purchase Commitment Excluding Longterm Commitment [Line Items]
Lease expiration date	Nov. 30, 2022
Leases extended expiration period	5 years
Aggregate tenant improvement allowance	$ 1.4
New Lease Agreement \| Letter of Credit
Purchase Commitment Excluding Longterm Commitment [Line Items]
Letter of credit amount	$ 0.8	$ 0.8	$ 0.8
Laboratory Facilities Lease
Purchase Commitment Excluding Longterm Commitment [Line Items]
Extended lease term date one		Jun. 30, 2020
Extended lease term date two		Dec. 31, 2020

Commitments and Contingencies - Schedule of Future Minimum Lease Payments Under Non-Cancellable Facility Leases and Non- Cancellable Purchase Commitment (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Commitments And Contingencies Disclosure [Abstract]
2019	$ 6,422
2020	27,070
2021	2,672
2022	2,518
Total minimum lease payments	$ 38,682

Stockholders' Equity - Additional Information (Details) - USD ($)		1 Months Ended				2 Months Ended	12 Months Ended
	Oct. 28, 2016	Jan. 31, 2019	May 31, 2018	Dec. 31, 2017	Aug. 31, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
At-the-Market Equity Offering Program
Class Of Stock [Line Items]
Common stock, value							$ 10,100,000
Common stock, shares issued and sold						5,294,902	1,799,504
Share price						$ 24.25
Gross proceeds from issuance of common stock						$ 128,400,000	$ 21,800,000
Underwriting discounts and commissions						7,700,000	700,000
Offering expense						300,000	100,000
Common stock, net proceeds						$ 120,400,000	$ 21,000,000
At-the-Market Equity Offering Program \| Cowen and Company LLC
Class Of Stock [Line Items]
Maximum amount of sales that agent may sell in shares of its common stock	$ 100,000,000
Percentage of gross sales proceeds of common stock payable as compensation	3.00%
Common stock, shares issued and sold								925,999
Share price				$ 12.42				$ 12.42
Gross proceeds from issuance of common stock								$ 11,500,000
Underwriting discounts and commissions								300,000
Offering expense								100,000
Common stock, net proceeds								11,100,000
At-the-Market Equity Offering Program \| Cowen and Company LLC \| Subsequent Event
Class Of Stock [Line Items]
Common stock, shares issued and sold		761,130
Common stock, net proceeds		$ 8,200,000
At-the-Market Equity Offering Program \| Weighted Average
Class Of Stock [Line Items]
Share price							$ 12.14
At-the-Market Equity Offering Program \| Weighted Average \| Cowen and Company LLC \| Subsequent Event
Class Of Stock [Line Items]
Share price		$ 11.17
Private Placement
Class Of Stock [Line Items]
Common stock, value								$ 81,810,000
Private Placement \| V-Sciences Investments Pte Ltd
Class Of Stock [Line Items]
Common stock, shares issued and sold					6,556,116
Share price					$ 11.4397
Gross proceeds from issuance of common stock					$ 75,000,000
Offering expense					100,000
Common stock, net proceeds					74,900,000
Additional shares of common stock available for purchase					$ 75,000,000
Private Placement \| KBI Biopharma, Inc
Class Of Stock [Line Items]
Common stock, shares issued and sold				776,104
Share price				$ 8.7746				$ 8.7746
Gross proceeds from issuance of common stock				$ 6,800,000
Purchase agreement, postponement fee not chargeable				4,100,000
Purchase agreement, campaign reservation fee not chargeable				2,700,000
Private Placement \| Maximum \| KBI Biopharma, Inc
Class Of Stock [Line Items]
Purchase agreement, contingent cash royalty payments				$ 700,000				$ 700,000
Underwritten Public Offering
Class Of Stock [Line Items]
Common stock, shares issued and sold			5,948,274
Gross proceeds from issuance of common stock			$ 86,300,000
Underwriting discounts and commissions			5,200,000
Offering expense			300,000
Common stock, net proceeds			$ 80,800,000
Closing stock, price per share			$ 14.50
Underwriters’ Option to Purchase Additional Shares
Class Of Stock [Line Items]
Common stock, shares issued and sold			775,861

Stock Option Plans and Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		12 Months Ended
	Aug. 31, 2017	Oct. 31, 2014	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares authorized			300,000,000	300,000,000
Share based payment options vested			$ 29,900	$ 29,400	$ 23,200
Options granted, weighted-average grant-date fair value			$ 7.77	$ 11.70	$ 13.32
Options exercised, aggregate intrinsic value			$ 4,900,000	$ 2,100,000	$ 15,800,000
Stock-based compensation expense			34,797,000	33,397,000	27,421,000
Unrecognized stock-based compensation expenses related to stock options			$ 49,700,000
Unrecognized share-based compensation related to stock options, RSUs and ESPP, period for recognition			2 years 7 months 6 days
Share based payment options grants			4,963,100
Weighted-average exercise price of options granted			$ 11.971
Expected dividend yield			$ 0
Inventory
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation capitalized			187,000
Research and Development Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 15,339,000	15,104,000	13,592,000
Non-cash stock-based compensation expense for option modifications				500,000
Selling, General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-cash stock-based compensation expense for option modifications				1,300,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
Options granted, expiration period			10 years
Stock-based compensation expense			$ 31,400,000	29,000,000	23,200,000
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 700,000	600,000
Unrecognized share-based compensation related to stock options, RSUs and ESPP, period for recognition			7 months 6 days
Total fair value of RSUs vested			$ 1,000,000	2,900,000
Total estimated grant date fair value			$ 78,000	$ 6,400,000
Estimated weighted-average grant-date fair value of RSUs granted			$ 15.60	$ 10.43
Unrecognized stock-based compensation expenses related to unvested RSUs			$ 300,000
Restricted Stock Units \| Vest After Twelve Months
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage from grant date	50.00%
Restricted Stock Units \| Vest After 18 Months
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage from grant date	25.00%
Restricted Stock Units \| Vest After 24 Months
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage from grant date	25.00%
Two Thousand Seventeen Bonus Payout Settled In Restricted Stock Units RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of RSUs vested				$ 2,700,000
Total estimated grant date fair value				4,300,000
Performance Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			500,000
Nonemployees Stock-Based Compensation
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 1,600,000	$ 1,900,000	$ 4,200,000
Share based payment options grants			147,500	60,000	248,650
Weighted-average exercise price of options granted			$ 14.32	$ 13.47	$ 18.16
2014 Equity Incentive Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of shares available for issuance			4.00%	4.00%
Common stock reserved for future issuance			388,873
2014 Equity Incentive Award Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated weighted-average grant-date fair value of RSUs granted			$ 15.600
2016 Employment Commencement Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			90,750			2,300,000
Common stock, shares authorized			2,300,000
2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			1,923,506
Stock-based compensation expense			$ 800,000	$ 80,000
Unrecognized share-based compensation related to stock options, RSUs and ESPP, period for recognition			5 months
Unrecognized stock-based compensation expenses related to unvested RSUs			$ 700,000
Percentage of purchase common stock of lesser of fair market value of common stock on first or last day of offering period by eligible employees			85.00%
Employee stock purchase plan offering period one		--05-16
Employee stock purchase plan offering period two		--11-16
2014 Employee Stock Purchase Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of shares reserve for issuance		1.00%
2014 Employee Stock Purchase Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of shares of common stock available for future issuance		320,000

Stock Option Plans and Stock-Based Compensation - Summary of Option Activities under 2016 and 2014 Plans (Details)	12 Months Ended
	Dec. 31, 2018 $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options, Beginning balance \| shares	11,406,219
Number of Options, Granted - at fair value \| shares	4,963,100
Number of Options, Exercised \| shares	(477,019)
Number of Options, Forfeited /cancelled \| shares	(1,217,747)
Number of Options, Ending balance \| shares	14,674,553
Weighted-Average Exercise Price, Beginning balance \| $ / shares	$ 15.321
Weighted-Average Exercise Price, Granted - at fair value \| $ / shares	11.971
Weighted-Average Exercise Price, Exercised \| $ / shares	4.513
Weighted-Average Exercise Price, Forfeited /cancelled \| $ / shares	19.389
Weighted-Average Exercise Price, Ending balance \| $ / shares	$ 14.202

Stock Option Plans and Stock-Based Compensation - Summary of Additional Information Related to Status of Options (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options outstanding, Number of Options	14,674,553	11,406,219
Options vested and expected to vest, Number of Options	14,674,553
Options vested and exercisable, Number of Options	8,531,888
Options outstanding, Weighted-Average Exercise Price	$ 14.202	$ 15.321
Options vested and expected to vest, Weighted-Average Exercise Price	14.202
Options vested and exercisable, Weighted-Average Exercise Price	$ 13.969
Options outstanding, Weighted-Average Contractual Terms	7 years 2 months 23 days
Options vested and expected to vest, Weighted-Average Contractual Terms	7 years 2 months 23 days
Options vested and exercisable, Weighted-Average Contractual Terms	6 years 1 month 9 days
Options outstanding, Aggregate Intrinsic Value	$ 22,368
Options vested and expected to vest, Aggregate Intrinsic Value	22,368
Options vested and exercisable, Aggregate Intrinsic Value	$ 22,365

Stock Option Plans and Stock-Based Compensation - Summary of RSU Activity, under 2014 Plan (Details) - Restricted Stock Units - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-Average Grant Date Fair Value, RSU's granted	$ 15.60	$ 10.43
2014 Equity Incentive Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of RSU's, Balances at December 31, 2017	120,377
Number of RSU's granted	5,000
Number of RSU's vested	(61,804)
Number of RSU's cancelled	(19,186)
Number of RSU's, Balances at December 31, 2018	44,387	120,377
Weighted-Average Grant Date Fair Value, Balances at December 31, 2017	$ 13.975
Weighted-Average Grant Date Fair Value, RSU's granted	15.600
Weighted-Average Grant Date Fair Value, RSU's Vested	18.622
Weighted-Average Grant Date Fair Value, RSU's cancelled	12.700
Weighted-Average Grant Date Fair Value, Balances at December 31, 2018	$ 12.700	$ 13.975

Stock Option Plans and Stock-Based Compensation - Schedule of Stock-Based Compensation Expense Reflected in Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 34,797	$ 33,397	$ 27,421
Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	15,339	15,104	13,592
General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 19,458	$ 18,293	$ 13,829

Stock Option Plans and Stock-Based Compensation - Schedule of Weighted Average Assumptions for Black-Scholes Option-Pricing Model Used in Determining Fair Value of Awards (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	6 months	6 months
Expected volatility	71.00%	68.00%
Risk-free interest rate	2.40%	1.42%
Expected dividend yield	0.00%	0.00%
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	6 years	6 years	6 years
Expected volatility	71.00%	76.00%	75.00%
Risk-free interest rate	2.77%	2.01%	1.42%
Expected dividend yield	0.00%	0.00%	0.00%

Restructuring - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended
	Jun. 30, 2017	Mar. 31, 2018	Dec. 31, 2018
Restructuring Cost And Reserve [Line Items]
Aggregate restructuring charges	$ 3,600,000
Payments for personnel-related restructuring charges		$ 2,100,000
Restructuring liabilities			$ 0
Research and Development Expense
Restructuring Cost And Reserve [Line Items]
Non-cash stock-based compensation expense	300,000
Selling, General and Administrative Expense
Restructuring Cost And Reserve [Line Items]
Non-cash stock-based compensation expense	1,200,000
Termination Severance and Related Costs \| Research and Development Expense
Restructuring Cost And Reserve [Line Items]
Aggregate restructuring charges	1,000,000
Termination Severance and Related Costs \| Selling, General and Administrative Expense
Restructuring Cost And Reserve [Line Items]
Aggregate restructuring charges	$ 1,100,000

Income Taxes - Components of Loss Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments [Abstract]
Domestic									$ (208,843)	$ (222,674)	$ (95,776)
Foreign									(496)	(15,496)	(31,561)
Net loss attributable to Coherus	$ (62,596)	$ (58,808)	$ (43,638)	$ (44,297)	$ (49,067)	$ (58,989)	$ (55,336)	$ (74,778)	$ (209,339)	$ (238,170)	$ (127,337)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Provision for (benefit from) income taxes	$ 0	$ 0	$ 0
U.S. federal corporate tax rate	21.00%	34.00%	34.00%
Gross increase of deferred tax assets	$ 2,900,000
Originally estimated remeasurement of deferred tax assets	87,900,000
Increase in valuation allowance	54,600,000	$ 4,600,000	$ 43,000,000
Unrecognized tax benefits, accrued interest and penalties accrued	0	0	0
Unrecognized tax benefits	18,115,000	$ 15,682,000	$ 18,682,000	$ 10,605,000
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 783,100,000
Net operating loss carryforwards expiration year	2031
Tax credit carryforwards	$ 44,100,000
Tax credit carryforwards expiration year	2031
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 49,100,000
Net operating loss carryforwards expiration year	2031
Tax credit carryforwards	$ 16,200,000
Maximum
Operating Loss Carryforwards [Line Items]
U.S. federal corporate tax rate		35.00%

Income Taxes - Reconciliation of Statutory U.S. Federal Rate (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Percent of pre-tax income:
U.S. federal statutory income tax rate	21.00%	34.00%	34.00%
State taxes, net of federal benefit	0.16%	0.80%	1.98%
Foreign rate differences	(0.05%)	(2.21%)	(8.43%)
Permanent items	0.15%	(0.19%)	(2.02%)
Research and development credit	2.61%	2.10%	8.38%
U.S. Tax Reform tax rate change	0.00%	(36.90%)	0.00%
Other	2.23%	(0.21%)	(0.13%)
Change in valuation allowance	(26.10%)	(1.94%)	(33.78%)
Effective income tax rate	0.00%	0.00%	0.00%
Accounting Standards Update 2016-09
Percent of pre-tax income:
Effect in NOLs due to adoption of ASU 2016-09	0.00%	4.55%	0.00%

Income Taxes - Components of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Components Of Deferred Tax Assets [Abstract]
Net operating loss carryforwards	$ 168,753	$ 134,420
Research and development credits	39,891	34,435
Depreciation and amortization	7,901	336
Stock-based compensation	17,123	13,119
Other accruals	3,942	655
Gross deferred tax assets	237,610	182,965
In-process research and development	(552)	(550)
Gross deferred tax liabilities	(552)	(550)
Total net deferred tax asset	237,058	182,415
Less valuation allowance	(237,058)	(182,415)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Balance at beginning of year	$ 15,682	$ 18,682	$ 10,605
Additions based on tax positions related to current year	1,276	3,387	6,111
Additions for tax positions of prior years	1,157	(6,387)	1,966
Balance at end of year	$ 18,115	$ 15,682	$ 18,682

Related Party Transactions - Additional Information (Details) - USD ($)	1 Months Ended		12 Months Ended
	Sep. 30, 2018	Feb. 28, 2014	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 29, 2016
Related Party Transaction [Line Items]
Accounts payable - related parties				$ 233,000
Research and development expense			$ 110,239,000	162,389,000	$ 254,440,000
Selling, general and administrative expenses from transactions with related party			181,000	62,000	178,000
Payments to acquire securities of non-controlling interest in subsidiary			300,000
RUSSIA \| InteKrin Therapeutics Inc
Related Party Transaction [Line Items]
Payments to acquire securities of non-controlling interest in subsidiary	$ 700,000
Percentage of securities acquired	17.50%
Mr. Lanfear \| RUSSIA \| InteKrin Therapeutics Inc
Related Party Transaction [Line Items]
Consideration received for shares	$ 400,000
InteKrin Therapeutics Inc
Related Party Transaction [Line Items]
Business combination consideration transferred		$ 5,000,000
Medpace Inc
Related Party Transaction [Line Items]
Prepaid assets				900,000
Accounts payable - related parties				200,000
Accrued and other liabilities				500,000
Research and development expense			1,500,000	8,200,000	34,600,000
Board of Directors \| Recruiting Services
Related Party Transaction [Line Items]
Research and development expense			130,000	17,000	135,000
Related party balances			0	0
Selling, general and administrative expenses from transactions with related party			$ 181,000	$ 62,000	$ 178,000
Affiliated Entity
Related Party Transaction [Line Items]
Aggregate principal amount						$ 25,000,000
Chief Executive Officer \| InteKrin Russia \| InteKrin Therapeutics Inc \| Mr. Lanfear
Related Party Transaction [Line Items]
Related party transaction ownership percentage		10.00%

Subsequent Events - Additional Information (Details) - USD ($)		3 Months Ended								12 Months Ended
	Jan. 07, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2020
Subsequent Event [Line Items]
Net sales		$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 1,395,000	$ 161,000			$ 0	$ 1,556,000	$ 189,476,000
Credit Agreement
Subsequent Event [Line Items]
Frequency of payments of borrowings description												Principal payments on the Borrowings are required to be paid in equal quarterly installments beginning on the four year anniversary of the Credit Agreement Closing Date (or, if consolidated net sales of UDENYCA™ in the fiscal year ending December 31, 2021 are less than $375.0 million, beginning on the three year anniversary of the Credit Agreement Closing Date), with the outstanding balance to be repaid on January 7, 2025 (the “Maturity Date”).
Debt instrument maturity date												Jan. 07, 2025
Consolidated net sales, 2020												$ 125,000,000
Consolidated net sales, thereafter												$ 150,000,000
Credit Agreement \| Paid on or Prior to the Three Year Anniversary of Closing Date
Subsequent Event [Line Items]
Prepayment premium, description												with respect to any prepayment paid or required to be paid on or prior to the three year anniversary of the Credit Agreement Closing Date, 5.00% of the Borrowings prepaid or required to be prepaid, plus all required interest payments that would have been due on the Borrowings prepaid or required to be prepaid through and including the three year anniversary of the Credit Agreement Closing Date
Prepayment premium percentage		5.00%										5.00%
Credit Agreement \| Paid after the Three Year but on or Prior to the Four Year Anniversary of Closing Date
Subsequent Event [Line Items]
Prepayment premium, description												with respect to any prepayment paid or required to be paid after the three year anniversary of the Credit Agreement Closing Date but on or prior to the four year anniversary of the Credit Agreement Closing Date, 5.00% of the Borrowings prepaid or required to be prepaid
Prepayment premium percentage		5.00%										5.00%
Credit Agreement \| Paid after the Four Year but on or Prior to the Five Year Anniversary of Closing Date
Subsequent Event [Line Items]
Prepayment premium, description												with respect to any prepayment paid or required to be paid after the four year anniversary of the Credit Agreement Closing Date but on or prior to the five year anniversary of the Credit Agreement Closing Date, 2.50% of the Borrowings prepaid or required to be prepaid
Prepayment premium percentage		2.50%										2.50%
Credit Agreement \| Paid Thereafter
Subsequent Event [Line Items]
Prepayment premium, description												with respect to any prepayment paid or required to be prepaid thereafter, 1.25% of the Borrowings prepaid or required to be prepaid
Prepayment premium percentage		1.25%										1.25%
Credit Agreement \| Minimum
Subsequent Event [Line Items]
Consolidated net sales, 2019												$ 70,000,000
Credit Agreement \| LIBOR
Subsequent Event [Line Items]
Convertible notes, effective interest rate		7.00%										7.00%
Credit Agreement \| Scenario Forecast \| Minimum
Subsequent Event [Line Items]
Net sales											$ 250,000,000
Credit Agreement \| Scenario Forecast \| Maximum
Subsequent Event [Line Items]
Net sales										$ 375,000,000
Credit Agreement \| Scenario Forecast \| LIBOR
Subsequent Event [Line Items]
Convertible notes, effective interest rate															6.75%
Credit Agreement \| Subsequent Event
Subsequent Event [Line Items]
Payment of closing fee to the lenders in form of origination issue discount	$ 1,100,000
Percentage required to pay an additional exit fee on principal amount	4.00%
HRP III Member \| Credit Agreement \| Subsequent Event
Subsequent Event [Line Items]
Term loan facility term	6 years
Line of credit facility, maximum borrowing capacity	$ 75,000,000

Supplementary Data - Quarterly Financial Data (Unaudited) - Schedule of Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 1,395	$ 161	$ 0	$ 1,556	$ 189,476
Total operating expenses	60,502	56,972	44,910	42,032	46,466	56,615	58,033	72,578	204,416	233,692	306,037
Net loss	(62,596)	(58,826)	(43,685)	(44,302)	(49,069)	(58,993)	(55,402)	(74,822)	(209,409)	(238,286)	(127,788)
Net loss attributable to Coherus	$ (62,596)	$ (58,808)	$ (43,638)	$ (44,297)	$ (49,067)	$ (58,989)	$ (55,336)	$ (74,778)	$ (209,339)	$ (238,170)	$ (127,337)
Net income (loss) per share attributable to Coherus:
Net loss per share attributable to Coherus, basic and diluted	$ (0.92)	$ (0.87)	$ (0.68)	$ (0.74)	$ (0.84)	$ (1.09)	$ (1.08)	$ (1.54)	$ (3.22)	$ (4.48)	$ (3.04)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

+ Details