Net Income Per Share - Computation of Basic and Diluted Net Income Per Share Attributable to the Company (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
Net income	$ 59,031	$ 23,567	$ 94,603	$ 3,563
Denominator:
Weighted-average common shares outstanding	71,099,773	69,479,016	70,880,979	69,310,791
Basic net income per share	$ 0.83	$ 0.34	$ 1.33	$ 0.05
Numerator:
Net income	$ 59,031	$ 23,567	$ 94,603	$ 3,563
Add interest expense on convertible notes, net of tax	3,454		5,936
Numerator for diluted net income per share attributable to Coherus	$ 62,485	$ 23,567	$ 100,539	$ 3,563
Denominator:
Denominator for basic net income per share	71,099,773	69,479,016	70,880,979	69,310,791
Stock options, including purchases from contributions to ESPP	3,208,580	3,469,172	3,437,358	2,953,049
Restricted stock units	104,092	15,784	96,163	17,724
Shares issuable upon conversion of convertible notes	14,247,835		9,360,853
Denominator for diluted net income per share attributable to Coherus	88,660,280	72,963,972	83,775,353	72,281,564
Diluted net income per share	$ 0.70	$ 0.32	$ 1.20	$ 0.05