Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jun. 17, 2021	Dec. 31, 2018
Class of Stock [Line Items]
Stock issuance costs		$ 33,198
Repurchase of convertible preferred stock (in shares)			547,000
Repurchase of convertible preferred stock			$ 662
Outstanding shares of convertible preferred stock converted into shares of common stock (in shares)					194,474,431
Convertible preferred stock outstanding (in shares)		0	194,474,000	152,116,000		74,406,000
Series C Convertible Preferred Stock
Class of Stock [Line Items]
Number of shares sold (in shares)	42,905,042
Sale of stock, price per share (in dollars per share)	$ 11.49
Proceeds from sale of stock, net of issuance costs	$ 492,500
Stock issuance costs	$ 500		$ 533
Series A Convertible Preferred Stock
Class of Stock [Line Items]
Stock issuance costs				$ 29
Repurchase of convertible preferred stock (in shares)	546,806
Repurchase of convertible preferred stock	$ 4,200		$ 700