CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands	Total		Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance at Dec. 31, 2020	$ 346,356		$ 1	$ 835,444	$ 5,208	$ (494,297)
Beginning balance, Shares at Dec. 31, 2020			143,820,000
Common stock issued upon vesting of restricted stock units, Shares			2,924,000
Common stock issued upon vesting of restricted stock units	0		$ 0	0	0	0
Cancellation of restricted stock awards, Shares			(64,000)
Cancellation of restricted stock awards	0		$ 0	0	0	0
Common stock issued upon stock option exercise, Shares			1,544,000
Common stock issued upon stock option exercise	21,531		$ 0	21,531	0	0
Common stock issued under employee stock purchase plan, Shares			246,000
Common stock issued under employee stock purchase plan	3,873		$ 0	3,873	0	0
Issuance of restricted stock awards, Shares			329,000
Issuance of restricted stock awards	0		$ 0	0	0	0
Stock-based compensation expense	75,432		0	75,432	0	0
Comprehensive loss	(3,570)	[1]	0	0	(3,570)	0
Net loss	(81,787)		0	0	0	(81,787)
Ending balance at Sep. 30, 2021	361,835		$ 1	936,280	1,638	(576,084)
Ending balance, Shares at Sep. 30, 2021			148,799,000
Beginning balance at Jun. 30, 2021	357,549		$ 1	907,383	3,346	(553,181)
Beginning balance, Shares at Jun. 30, 2021			147,498,000
Common stock issued upon vesting of restricted stock units, Shares			931,000
Common stock issued upon vesting of restricted stock units	0		$ 0	0	0	0
Common stock issued upon stock option exercise, Shares			315,000
Common stock issued upon stock option exercise	3,773		$ 0	3,773	0	0
Issuance of restricted stock awards, Shares			55,000
Issuance of restricted stock awards	0		$ 0	0	0	0
Stock-based compensation expense	25,124		0	25,124	0	0
Comprehensive loss	(1,708)	[1]	0	0	(1,708)	0
Net loss	(22,903)		0	0	0	(22,903)
Ending balance at Sep. 30, 2021	361,835		$ 1	936,280	1,638	(576,084)
Ending balance, Shares at Sep. 30, 2021			148,799,000
Beginning balance at Dec. 31, 2021	354,474		$ 2	971,604	414	(617,546)
Beginning balance, Shares at Dec. 31, 2021			150,398,000
Common stock issued upon vesting of restricted stock units, Shares			2,995,000
Common stock issued upon vesting of restricted stock units	0		$ 0	0	0	0
Repurchases of common stock, Shares			(6,596,000)
Repurchases of common stock, Value	$ (83,487)		$ (1)	(83,486)	0	0
Cancellation of restricted stock awards, Shares			(227,000)
Common stock issued upon stock option exercise, Shares	206,132		206,000
Common stock issued upon stock option exercise	$ 2,827		$ 0	2,827	0	0
Common stock issued under employee stock purchase plan, Shares			268,000
Common stock issued under employee stock purchase plan	2,751		$ 0	2,751	0	0
Issuance of restricted stock awards, Shares			1,031,000
Issuance of restricted stock awards	0		$ 0	0	0	0
Issuance of performance stock awards, Shares			361,000
Issuance of performance stock awards	0		$ 0	0	0	0
Stock-based compensation expense	78,083		0	78,083	0	0
Comprehensive loss	(8,008)	[1]	0	0	(8,008)	0
Net loss	(86,258)		0	0	0	(86,258)
Ending balance at Sep. 30, 2022	260,382		$ 1	971,779	(7,594)	(703,804)
Ending balance, Shares at Sep. 30, 2022			148,436,000
Beginning balance at Jun. 30, 2022	274,276		$ 1	961,978	(4,229)	(683,474)
Beginning balance, Shares at Jun. 30, 2022			149,233,000
Common stock issued upon vesting of restricted stock units, Shares			1,047,000
Common stock issued upon vesting of restricted stock units	0		$ 0	0	0	0
Repurchases of common stock, Shares			(1,617,000)
Repurchases of common stock, Value	(14,990)		$ 0	(14,990)	0	0
Cancellation of restricted stock awards, Shares			(227,000)
Stock-based compensation expense	24,791		$ 0	24,791	0	0
Comprehensive loss	(3,365)	[1]	0	0	(3,365)	0
Net loss	(20,330)		0	0	0	(20,330)
Ending balance at Sep. 30, 2022	$ 260,382		$ 1	$ 971,779	$ (7,594)	$ (703,804)
Ending balance, Shares at Sep. 30, 2022			148,436,000

[1] Net of tax effect which was not material.