Equity Incentive Plans - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Number of Shares Outstanding, Beginning Balance	884	944	1,115
Number of Shares, Exercised	(533)	(10)	(49)
Number of Shares, Forfeited or cancelled		(50)	(122)
Number of Shares Outstanding, Ending Balance	351	884	944
Number of Shares, Vested and Exercisable	351
Weighted-Average Exercise Price, Beginning Balance	$ 2.17	$ 2.20	$ 2.45
Weighted-Average Exercise Price, Exercised	2.09	1.92	1.75
Weighted-Average Exercise Price, Forfeited or cancelled		2.87	4.65
Weighted-Average Exercise Price, Ending Balance	2.28	$ 2.17	$ 2.20
Weighted-Average Exercise Price, Vested and Exercisable	$ 2.28
Weighted-Average Remaining Contractual Life (Years)	11 months 26 days
Weighted-Average Remaining Contractual Life (Years), Vested and Exercisable	11 months 26 days
Aggregate Intrinsic Value Outstanding, Beginning Balance	$ 722	$ 627	$ 970
Aggregate Intrinsic Value, Exercised	1,559	11	70
Aggregate Intrinsic Value Outstanding, Ending Balance	1,577	$ 722	$ 627
Aggregate Intrinsic Value, Vested and Exercisable	$ 1,577