Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Total revenue	$ 30,033	$ 29,218	$ 129,453	$ 80,755
Operating costs and expenses:
Cost of goods sold	5,570	4,927	15,154	15,385
Research and development	100,531	99,048	305,954	324,197
General and administrative	26,982	23,983	77,546	71,570
Impairment of assets and other costs for terminated program	0	0	45,189	0
Total operating costs and expenses	133,083	127,958	443,843	411,152
Loss from operations	(103,050)	(98,740)	(314,390)	(330,397)
Non-operating income (expense):
Interest expense	0	(5,425)	(6,851)	(15,882)
Non-cash interest expense on liability related to sale of future royalties	(8,425)	(5,813)	(22,084)	(17,853)
Interest income and other income (expense), net	2,910	11,492	16,453	35,964
Total non-operating income (expense), net	(5,515)	254	(12,482)	2,229
Loss before provision for income taxes	(108,565)	(98,486)	(326,872)	(328,168)
Provision for income taxes	21	99	365	335
Net loss	$ (108,586)	$ (98,585)	$ (327,237)	$ (328,503)
Basic and diluted net loss per share (in dollars per share)	$ (0.61)	$ (0.56)	$ (1.84)	$ (1.88)
Weighted average shares outstanding used in computing basic and diluted net loss per share (in shares)	179,090	175,402	178,203	174,609
Product sales
Revenue:
Total revenue	$ 5,691	$ 5,558	$ 14,620	$ 14,302
Royalty revenue
Revenue:
Total revenue	12,289	10,275	31,411	29,008
Non-cash royalty revenue related to sale of future royalties
Revenue:
Total revenue	10,422	10,264	28,001	27,585
License, collaboration and other revenue
Revenue:
Total revenue	$ 1,631	$ 3,121	$ 55,421	$ 9,860