Condensed Consolidated Statements of Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Note Receivable [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]
Beginning Balance at Dec. 31, 2020	$ 385,613	$ 69	$ 870,788	$ (16)	$ 114	$ (485,342)
Beginning Balance, shares at Dec. 31, 2020		69,452,466
Net loss	(68,920)					(68,920)
Unrealized loss on investments	(195)				(195)
Issuance of common stock under equity incentive and employee stock purchase plans	3,262	$ 1	3,261
Issuance of common stock under equity incentive and employee stock purchase plans, shares		519,852
Repurchased shares upon vesting of restricted stock units for tax withholdings	(5,273)		(5,273)
Repurchased shares upon vesting of restricted stock units for tax withholdings, shares		(86,343)
Employee stock-based compensation	15,294		15,294
Compensation expense related to options granted to consultants	489		489
Ending Balance at Jun. 30, 2021	330,270	$ 70	884,559	(16)	(81)	(554,262)
Ending Balance, shares at Jun. 30, 2021		69,885,975
Beginning Balance at Mar. 31, 2021	361,004	$ 70	876,017	(16)	(14)	(515,053)
Beginning Balance, shares at Mar. 31, 2021		69,742,493
Net loss	(39,209)					(39,209)
Unrealized loss on investments	(67)				(67)
Issuance of common stock under equity incentive and employee stock purchase plans	1,099		1,099
Issuance of common stock under equity incentive and employee stock purchase plans, shares		148,865
Repurchased shares upon vesting of restricted stock units for tax withholdings	(260)		(260)
Repurchased shares upon vesting of restricted stock units for tax withholdings, shares		(5,383)
Employee stock-based compensation	7,454		7,454
Compensation expense related to options granted to consultants	249		249
Ending Balance at Jun. 30, 2021	330,270	$ 70	884,559	(16)	(81)	(554,262)
Ending Balance, shares at Jun. 30, 2021		69,885,975
Beginning Balance at Dec. 31, 2021	$ 286,120	$ 70	903,646	(16)	(483)	(617,097)
Beginning Balance, shares at Dec. 31, 2021	70,357,557	70,357,557
Net loss	$ (70,259)					(70,259)
Unrealized loss on investments	(1,827)				(1,827)
Issuance of common stock upon net exercise of warrant		66,833
Issuance of common stock under equity incentive and employee stock purchase plans	8,061	$ 1	8,060
Issuance of common stock under equity incentive and employee stock purchase plans, shares		1,006,303
Repurchased shares upon vesting of restricted stock units for tax withholdings	(3,126)		(3,126)
Repurchased shares upon vesting of restricted stock units for tax withholdings, shares		(85,855)
Employee stock-based compensation	17,054		17,054
Compensation expense related to options granted to consultants	507		507
Ending Balance at Jun. 30, 2022	$ 236,530	$ 71	926,141	(16)	(2,310)	(687,356)
Ending Balance, shares at Jun. 30, 2022	71,344,838	71,344,838
Beginning Balance at Mar. 31, 2022	$ 258,719	$ 71	916,224	(16)	(1,855)	(655,705)
Beginning Balance, shares at Mar. 31, 2022		71,142,102
Net loss	(31,651)					(31,651)
Unrealized loss on investments	(455)				(455)
Issuance of common stock under equity incentive and employee stock purchase plans	1,782		1,782
Issuance of common stock under equity incentive and employee stock purchase plans, shares		202,736
Employee stock-based compensation	7,872		7,872
Compensation expense related to options granted to consultants	263		263
Ending Balance at Jun. 30, 2022	$ 236,530	$ 71	$ 926,141	$ (16)	$ (2,310)	$ (687,356)
Ending Balance, shares at Jun. 30, 2022	71,344,838	71,344,838