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	0		$ 0	0	0	0
Common stock issued upon vesting of restricted stock units, Shares			1,993,000
Common stock issued upon stock option exercise	17,758		$ 0	17,758	0	0
Common stock issued upon stock option exercise, Shares			1,229,000
Common stock issued under employee stock purchase plan	3,873		$ 0	3,873	0	0
Common stock issued under employee stock purchase plan, shares			246,000
Issuance of restricted stock awards	0		$ 0	0	0	0
Issuance of restricted stock awards, Shares			274,000
Cancellation of restricted stock awards	0		$ 0	0	0	0
Cancellation of restricted stock awards, Shares			(64,000)
Stock-based compensation expense	50,308		$ 0	50,308	0	0
Comprehensive loss	(1,862)	[1]	0	0	(1,862)	0
Net loss	(58,884)		0	0	0	(58,884)
Ending balance at Jun. 30, 2021	357,549		$ 1	907,383	3,346	(553,181)
Ending balance, Shares at Jun. 30, 2021			147,498,000
Beginning Balance at Mar. 31, 2021	347,486		$ 1	869,174	2,255	(523,944)
Beginning balance, Shares at Mar. 31, 2021			145,638,000
Common stock issued upon vesting of restricted stock units	0		$ 0	0	0	0
Common stock issued upon vesting of restricted stock units, Shares			1,026,000
Common stock issued upon stock option exercise	8,186		$ 0	8,186	0	0
Common stock issued upon stock option exercise, Shares			588,000
Common stock issued under employee stock purchase plan	3,873		$ 0	3,873	0	0
Common stock issued under employee stock purchase plan, shares			246,000
Stock-based compensation expense	26,150		$ 0	26,150	0	0
Comprehensive loss	1,091	[1]	0	0	1,091	0
Net loss	(29,237)		0	0	0	(29,237)
Ending balance at Jun. 30, 2021	357,549		$ 1	907,383	3,346	(553,181)
Ending balance, Shares at Jun. 30, 2021			147,498,000
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	0		$ 0	0	0	0
Common stock issued upon vesting of restricted stock units, Shares			1,948,000
Common stock issued upon stock option exercise	$ 2,827		$ 0	2,827	0	0
Common stock issued upon stock option exercise, Shares	206,132		206,000
Common stock issued under employee stock purchase plan	$ 2,751		$ 0	2,751	0	0
Common stock issued under employee stock purchase plan, shares			268,000
Issuance of restricted stock awards	0		$ 0	0	0	0
Issuance of restricted stock awards, Shares			1,031,000
Issuance of performance stock awards	0		$ 0	0	0	0
Issuance of performance stock awards, shares			361,000
Repurchases of common stock, Shares			(4,979,000)
Repurchases of common stock, Value	(68,497)		$ (1)	(68,496)	0	0
Stock-based compensation expense	53,292		0	53,292	0	0
Comprehensive loss	(4,643)	[1]	0	0	(4,643)	0
Net loss	(65,928)		0	0	0	(65,928)
Ending balance at Jun. 30, 2022	274,276		$ 1	961,978	(4,229)	(683,474)
Ending balance, Shares at Jun. 30, 2022			149,233,000
Beginning Balance at Mar. 31, 2022	309,020		$ 2	964,474	(533)	(654,923)
Beginning balance, Shares at Mar. 31, 2022			150,420,000
Common stock issued upon vesting of restricted stock units	0		$ 0	0	0	0
Common stock issued upon vesting of restricted stock units, Shares			1,071,000
Common stock issued upon stock option exercise	554		$ 0	554	0	0
Common stock issued upon stock option exercise, Shares			42,000
Common stock issued under employee stock purchase plan	2,751		$ 0	2,751	0	0
Common stock issued under employee stock purchase plan, shares			268,000
Repurchases of common stock, Shares			(2,568,000)
Repurchases of common stock, Value	(32,121)		$ (1)	(32,120)	0	0
Stock-based compensation expense	26,319		0	26,319	0	0
Comprehensive loss	(3,696)	[1]	0	0	(3,696)	0
Net loss	(28,551)		0	0	0	(28,551)
Ending balance at Jun. 30, 2022	$ 274,276		$ 1	$ 961,978	$ (4,229)	$ (683,474)
Ending balance, Shares at Jun. 30, 2022			149,233,000

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