CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (UNAUDITED) - USD ($) $ in Thousands	Total	Non Restricted Common Stock [Member]	Common Stock [Member]	Common Stock [Member] Non Restricted Common Stock [Member]	Preferred Stock [Member] Convertible Preferred Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Non Restricted Common Stock [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]
Balances at Dec. 31, 2020	$ (65,249)		$ 1		$ 169,548		$ 154		$ 0	$ (65,319)
Balances, shares at Dec. 31, 2020			5,593,240		12,647,934
Treasury stock, shares at Dec. 31, 2020						22,600,000
Treasury stock at Dec. 31, 2020						$ (85)
Stock-based compensation expense	587						587
Unrealized gain on available-for-sale securities, net of tax	0
Net loss	(38,700)									(38,700)
Balances at Mar. 31, 2021	(103,362)		$ 1		$ 169,548		741			(104,019)
Balances, shares at Mar. 31, 2021			5,593,240		12,647,934
Treasury stock, shares at Mar. 31, 2021						22,600,000
Treasury stock at Mar. 31, 2021						$ (85)
Balances at Dec. 31, 2021	$ 558,019		$ 11		$ 0		850,125		(8)	(292,109)
Balances, shares at Dec. 31, 2021			110,782,909		0
Treasury stock, shares at Dec. 31, 2021	468,751					468,751
Treasury stock at Dec. 31, 2021	$ 0					$ 0
Repurchase of unvested restricted common stock			1,158,089			(1,158,089)
Vesting of restricted common stock from early-exercised options	1						1
Exercise of stock options, shares				50,353
Exercise of stock options		$ 47						$ 47
Stock-based compensation expense	1,983						1,983
Retirement of treasury shares, shares						(1,626,840)
Unrealized gain on available-for-sale securities, net of tax	8								8
Net loss	(100,666)									(100,666)
Balances at Mar. 31, 2022	$ 459,392		$ 11		$ 0		$ 852,156		$ 0	$ (392,775)
Balances, shares at Mar. 31, 2022			109,675,173		0
Treasury stock, shares at Mar. 31, 2022	0					0
Treasury stock at Mar. 31, 2022	$ 0					$ 0