Stock-Based Compensation - Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Stock Incentive Plan
Number of Options
Beginning balance (in shares)	0
Granted (in shares)	4,347,492
Exercised (in shares)	0
Cancelled/forfeited (in shares)	0
Ending balance (in shares)	4,347,492	0
Weighted Average Exercise Price
Granted (in dollars per share)	$ 5.15
Options outstanding, end of period, weighted average exercise price (in dollars per share)	$ 5.15
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual life, outstanding	9 years 9 months 14 days
Aggregate intrinsic value, outstanding	$ 498
Equity Incentive Plan
Number of Options
Beginning balance (in shares)	31,962,921
Granted (in shares)	0
Exercised (in shares)	(268,702)
Cancelled/forfeited (in shares)	(1,049,835)
Ending balance (in shares)	30,644,384	31,962,921
Weighted Average Exercise Price
Options outstanding, beginning of period, weighted average exercise price (in dollars per share)	$ 2.81
Exercised (in dollars per share)	2.50
Cancelled/forfeited (in dollars per share)	3.40
Options outstanding, end of period, weighted average exercise price (in dollars per share)	$ 2.79	$ 2.81
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual life, outstanding	7 years 4 months 2 days	7 years 9 months 7 days
Aggregate Intrinsic Value, Exercised	$ 729
Aggregate intrinsic value, outstanding	$ 73,051	$ 86,075
STI Plan
Number of Options
Beginning balance (in shares)	9,526,727
Granted (in shares)	0
Exercised (in shares)	(492,973)
Cancelled/forfeited (in shares)	(243,815)
Ending balance (in shares)	8,789,939	9,526,727
Weighted Average Exercise Price
Options outstanding, beginning of period, weighted average exercise price (in dollars per share)	$ 5.55
Exercised (in dollars per share)	2.41
Cancelled/forfeited (in dollars per share)	8.02
Options outstanding, end of period, weighted average exercise price (in dollars per share)	$ 5.74	$ 5.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual life, outstanding	8 years 4 months 24 days	8 years
Aggregate Intrinsic Value, Exercised	$ 1,037
Aggregate intrinsic value, outstanding	$ 10,759	$ 13,905