Stock-Based Compensation - Early Exercise Of Stock Options (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Stock-Based Compensation
Early exercised stock options, Unvested balance at beginning of period	182	755	912
Early exercised			471
Vested	(153)	(306)	(628)
Forfeited		(267)
Early exercised stock options, Unvested balance at end of period	29	182	755