Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	At The Market Offering	Total
Balance, beginning of period at Dec. 31, 2020	$ 6	$ 1,058,823	$ (46)	$ (665,197)		$ 393,586
Balance, beginning of period (in shares) at Dec. 31, 2020	62,563,457
Statement of Stockholders' Equity (Deficit)
Issuance of common stock for public offering	$ 1	249,458				249,459
Issuance of common stock for public offering (in shares)	4,025,000
Issuance of common stock for success payment		27,500				27,500
Issuance of common stock for success payment (in shares)	303,599
Exercise of stock options		12,002				12,002
Exercise of stock options (in shares)	501,162
Vesting of restricted common stock awards (in shares)	79,397
Stock-based compensation expense		12,204				12,204
Unrealized gain (loss) on marketable debt securities			(27)			(27)
Net loss				(56,728)		(56,728)
Balance, end of period at Mar. 31, 2021	$ 7	1,359,987	(73)	(721,925)		637,996
Balance, end of period (in shares) at Mar. 31, 2021	67,472,615
Balance, beginning of period at Dec. 31, 2020	$ 6	1,058,823	(46)	(665,197)		393,586
Balance, beginning of period (in shares) at Dec. 31, 2020	62,563,457
Statement of Stockholders' Equity (Deficit)
Net loss						(151,066)
Balance, end of period at Sep. 30, 2021	$ 7	1,403,114	(64)	(816,263)		586,794
Balance, end of period (in shares) at Sep. 30, 2021	68,320,659
Balance, beginning of period at Mar. 31, 2021	$ 7	1,359,987	(73)	(721,925)		637,996
Balance, beginning of period (in shares) at Mar. 31, 2021	67,472,615
Statement of Stockholders' Equity (Deficit)
Exercise of stock options		16,567				16,567
Exercise of stock options (in shares)	629,973
Vesting of restricted common stock awards (in shares)	37,790
Stock-based compensation expense		13,526				13,526
Purchase of common stock under benefit plans		526				526
Purchase of common stock under benefit plans (in shares)	19,408
Unrealized gain (loss) on marketable debt securities			2			2
Net loss				(55,256)		(55,256)
Balance, end of period at Jun. 30, 2021	$ 7	1,390,606	(71)	(777,181)		613,361
Balance, end of period (in shares) at Jun. 30, 2021	68,159,786
Statement of Stockholders' Equity (Deficit)
Exercise of stock options		2,496				2,496
Exercise of stock options (in shares)	86,985
Vesting of restricted common stock awards (in shares)	73,888
Stock-based compensation expense		10,012				10,012
Unrealized gain (loss) on marketable debt securities			7			7
Net loss				(39,082)		(39,082)
Balance, end of period at Sep. 30, 2021	$ 7	1,403,114	(64)	(816,263)		586,794
Balance, end of period (in shares) at Sep. 30, 2021	68,320,659
Balance, beginning of period at Dec. 31, 2021	$ 7	1,411,827	(493)	(857,699)		553,642
Balance, beginning of period (in shares) at Dec. 31, 2021	68,435,257
Statement of Stockholders' Equity (Deficit)
Exercise of stock options		218				218
Exercise of stock options (in shares)	12,573
Vesting of restricted common stock awards (in shares)	154,834
Stock-based compensation expense		11,431				11,431
Unrealized gain (loss) on marketable debt securities			(2,016)			(2,016)
Net loss				(50,515)		(50,515)
Balance, end of period at Mar. 31, 2022	$ 7	1,423,476	(2,509)	(908,214)		512,760
Balance, end of period (in shares) at Mar. 31, 2022	68,602,664
Balance, beginning of period at Dec. 31, 2021	$ 7	1,411,827	(493)	(857,699)		553,642
Balance, beginning of period (in shares) at Dec. 31, 2021	68,435,257
Statement of Stockholders' Equity (Deficit)
Issuance of common stock for public offering (in shares)					0
Net loss						(159,694)
Balance, end of period at Sep. 30, 2022	$ 7	1,436,422	(4,291)	(1,017,393)		414,745
Balance, end of period (in shares) at Sep. 30, 2022	68,761,729
Balance, beginning of period at Mar. 31, 2022	$ 7	1,423,476	(2,509)	(908,214)		512,760
Balance, beginning of period (in shares) at Mar. 31, 2022	68,602,664
Statement of Stockholders' Equity (Deficit)
Exercise of stock options (in shares)	20
Vesting of restricted common stock awards (in shares)	77,884
Stock-based compensation expense		6,618				6,618
Purchase of common stock under benefit plans		367				367
Purchase of common stock under benefit plans (in shares)	37,866
Unrealized gain (loss) on marketable debt securities			(878)			(878)
Net loss				(53,453)		(53,453)
Balance, end of period at Jun. 30, 2022	$ 7	1,430,461	(3,387)	(961,667)		465,414
Balance, end of period (in shares) at Jun. 30, 2022	68,718,434
Statement of Stockholders' Equity (Deficit)
Exercise of stock options		80				80
Exercise of stock options (in shares)	4,976
Vesting of restricted common stock awards (in shares)	38,319
Stock-based compensation expense		5,881				5,881
Unrealized gain (loss) on marketable debt securities			(904)			(904)
Net loss				(55,726)		(55,726)
Balance, end of period at Sep. 30, 2022	$ 7	$ 1,436,422	$ (4,291)	$ (1,017,393)		$ 414,745
Balance, end of period (in shares) at Sep. 30, 2022	68,761,729