Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues [Abstract]
Product sales, net	$ 47,555	$ 31,501	$ 86,598	$ 45,619
Costs and operating expenses:
Cost of sales	748	377	1,332	512
Research and development	51,784	34,085	102,641	73,858
Selling, general and administrative	61,093	49,075	120,059	96,736
Total costs and operating expenses	113,625	83,537	224,032	171,106
Loss from operations	(66,070)	(52,036)	(137,434)	(125,487)
Other income (expense):
Interest income	164	1,514	493	4,370
Interest expense	(3,677)	(2,282)	(7,366)	(4,596)
Other expenses, net	(9)	(36)	(215)	(153)
Total other income, net	(3,522)	(804)	(7,088)	(379)
Net loss	(69,592)	(52,840)	(144,522)	(125,866)
Other comprehensive loss:
Net unrealized gain (loss) on marketable securities, net of tax	(78)	12	(259)	472
Cumulative translation adjustment	259	0	259	0
Comprehensive loss	$ (69,411)	$ (52,828)	$ (144,522)	$ (125,394)
Basic and diluted net loss per common share	$ (1.12)	$ (0.86)	$ (2.32)	$ (2.06)
Weighted-average number of shares used in computing basic and diluted net loss per common share	62,312,418	62,207,328	61,116,707	60,952,269