Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	At The Market Offering	Common Stock	Common Stock At The Market Offering	Additional Paid-in Capital	Additional Paid-in Capital At The Market Offering	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning balance at Dec. 31, 2020	$ 462,339		$ 8		$ 1,586,616		$ 296	$ (1,124,581)
Beginning balance (in shares) at Dec. 31, 2020			83,372,000
Issuance of common stock, net of commissions and offering costs, value	1,749	$ 2,382			1,749	$ 2,382
Issuance of common stock, net of commissions and offering costs, shares				146,000
RSU settlements, net of shares withheld	(1,231)				(1,231)
RSU settlements, net of shares withheld, shares			449,000
Issuance of common stock pursuant to employee stock awards, shares			108,000
Stock-based compensation expense	12,268				12,268
Net income (loss)	(78,335)							(78,335)
Unrealized gain (loss) on available-for-sale securities	(135)						(135)
Ending balance at Mar. 31, 2021	399,037		$ 8		1,601,784		161	(1,202,916)
Ending balance (in shares) at Mar. 31, 2021			84,075,000
Beginning balance at Dec. 31, 2020	462,339		$ 8		1,586,616		296	(1,124,581)
Beginning balance (in shares) at Dec. 31, 2020			83,372,000
Net income (loss)	(246,792)
Unrealized gain (loss) on available-for-sale securities	(272)
Ending balance at Sep. 30, 2021	310,141		$ 9		1,681,481		24	(1,371,373)
Ending balance (in shares) at Sep. 30, 2021			88,387,000
Beginning balance at Mar. 31, 2021	399,037		$ 8		1,601,784		161	(1,202,916)
Beginning balance (in shares) at Mar. 31, 2021			84,075,000
RSU settlements, net of shares withheld	(13)				(13)
RSU settlements, net of shares withheld, shares			423,000
Issuance of common stock pursuant to employee stock awards	2,599				2,599
Issuance of common stock pursuant to employee stock awards, shares			256,000
Stock-based compensation expense	13,807				13,807
Net income (loss)	(83,793)							(83,793)
Unrealized gain (loss) on available-for-sale securities	(99)						(99)
Ending balance at Jun. 30, 2021	331,538		$ 8		1,618,177		62	(1,286,709)
Ending balance (in shares) at Jun. 30, 2021			84,754,000
Issuance of common stock, net of commissions and offering costs, value	48,701		$ 1		48,700
Issuance of common stock, net of commissions and offering costs, shares			3,259,000
RSU settlements, net of shares withheld, shares			306,000
Issuance of common stock pursuant to employee stock awards	842				842
Issuance of common stock pursuant to employee stock awards, shares			68,000
Stock-based compensation expense	13,762				13,762
Net income (loss)	(84,664)							(84,664)
Unrealized gain (loss) on available-for-sale securities	(38)						(38)
Ending balance at Sep. 30, 2021	310,141		$ 9		1,681,481		24	(1,371,373)
Ending balance (in shares) at Sep. 30, 2021			88,387,000
Beginning balance at Dec. 31, 2021	279,614		$ 9		1,744,695		(368)	(1,464,722)
Beginning balance (in shares) at Dec. 31, 2021			91,671,000
Issuance of common stock, net of commissions and offering costs, value		$ 20,516				$ 20,516
Issuance of common stock, net of commissions and offering costs, shares				1,320,000
RSU settlements, net of shares withheld	(616)				(616)
RSU settlements, net of shares withheld, shares			405,000
Issuance of common stock pursuant to employee stock awards	96				96
Issuance of common stock pursuant to employee stock awards, shares			10,000
Stock-based compensation expense	14,335				14,335
Net income (loss)	(88,105)							(88,105)
Unrealized gain (loss) on available-for-sale securities	(1,524)						(1,524)
Ending balance at Mar. 31, 2022	224,316		$ 9		1,779,026		(1,892)	(1,552,827)
Ending balance (in shares) at Mar. 31, 2022			93,406,000
Beginning balance at Dec. 31, 2021	279,614		$ 9		1,744,695		(368)	(1,464,722)
Beginning balance (in shares) at Dec. 31, 2021			91,671,000
Net income (loss)	(153,730)
Unrealized gain (loss) on available-for-sale securities	(2,591)
Ending balance at Sep. 30, 2022	187,113		$ 9		1,808,515		(2,959)	(1,618,452)
Ending balance (in shares) at Sep. 30, 2022			94,879,000
Beginning balance at Mar. 31, 2022	224,316		$ 9		1,779,026		(1,892)	(1,552,827)
Beginning balance (in shares) at Mar. 31, 2022			93,406,000
RSU settlements, net of shares withheld	(3)				(3)
RSU settlements, net of shares withheld, shares			647,000
Issuance of common stock pursuant to employee stock awards	1,309				1,309
Issuance of common stock pursuant to employee stock awards, shares			303,000
Stock-based compensation expense	14,117				14,117
Net income (loss)	18,466							18,466
Unrealized gain (loss) on available-for-sale securities	(726)						(726)
Ending balance at Jun. 30, 2022	257,479		$ 9		1,794,449		(2,618)	(1,534,361)
Ending balance (in shares) at Jun. 30, 2022			94,356,000
RSU settlements, net of shares withheld	(4)				(4)
RSU settlements, net of shares withheld, shares			517,000
Issuance of common stock pursuant to employee stock awards	47				47
Issuance of common stock pursuant to employee stock awards, shares			6,000
Stock-based compensation expense	14,023				14,023
Net income (loss)	(84,091)							(84,091)
Unrealized gain (loss) on available-for-sale securities	(341)						(341)
Ending balance at Sep. 30, 2022	$ 187,113		$ 9		$ 1,808,515		$ (2,959)	$ (1,618,452)
Ending balance (in shares) at Sep. 30, 2022			94,879,000