Stock-based Compensation - Recognized and Unamortized Expense (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Share-based Compensation
Total stock-based compensation expense	$ 1,909	$ 1,448
Total unamortized stock-based compensation expense	$ 19,207		$ 11,960
Weighted average period over which expense is to be recognized	2 years 10 months 24 days		2 years 10 months 24 days
RSU awards
Share-based Compensation
Total stock-based compensation expense	$ 1,176	1,230
Total unamortized stock-based compensation expense	12,838		$ 10,204
PSU awards
Share-based Compensation
Total stock-based compensation expense	412	60
Total unamortized stock-based compensation expense	5,544		1,547
DSU awards
Share-based Compensation
Total stock-based compensation expense	226	$ 158
Total unamortized stock-based compensation expense	825		$ 209
2021 ESPP
Share-based Compensation
Total stock-based compensation expense	$ 95

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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