Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Redeemable Convertible Preferred Stock	Common Stock [Member] Class A and Class B common stock	Additional Paid-in Capital	Accumulated Deficit
Beginning balance at Dec. 31, 2020	$ (67,120)			$ 37,704	$ (104,824)
Beginning balance, Shares at Dec. 31, 2020			27,924,000
Temporary equity, beginning balance, Shares at Dec. 31, 2020		61,717,000
Temporary equity, beginning balance at Dec. 31, 2020		$ 187,811
Stock-based compensation expense	2,628			2,628
Exercise of stock options	1,488			1,488
Exercise of stock options, Shares			1,226,000
Vesting of early exercised stock options	179			179
Net loss	(6,439)				(6,439)
Ending balance at Mar. 31, 2021	(69,264)			41,999	(111,263)
Ending balance, Shares at Mar. 31, 2021			29,150,000
Temporary equity, ending balance, Shares at Mar. 31, 2021		61,717,000
Temporary equity, ending balance at Mar. 31, 2021		$ 187,811
Beginning balance at Dec. 31, 2021	306,548		$ 1	486,354	(179,807)
Beginning balance, Shares at Dec. 31, 2021			109,876,000
Stock-based compensation expense	13,785			13,785
Exercise of stock options	$ 3,977			3,977
Exercise of stock options, Shares	1,603,403		1,603,000
Vesting of restricted stock units, Shares			31,000
Vesting of early exercised stock options	$ 743			743
Donation of common stock and repurchase of unvested stock options, Shares			(3,000)
Cumulative impact of Topic 842 adoption	17				17
Net loss	(22,220)				(22,220)
Ending balance at Mar. 31, 2022	$ 302,849		$ 1	$ 504,859	$ (202,011)
Ending balance, Shares at Mar. 31, 2022			111,507,000