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

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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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Stock-Based Compensation - Recognized and Unamortized Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Share-based Compensation
Total stock-based compensation expense	$ 2,336	$ 2,437	$ 4,245	$ 3,885
Total unamortized stock-based compensation expense	16,814		$ 16,814		$ 11,960
Weighted average period over which expense is to be recognized			2 years 9 months 18 days		2 years 10 months 24 days
RSU awards
Share-based Compensation
Total stock-based compensation expense	1,273	1,816	$ 2,449	3,046
Total unamortized stock-based compensation expense	11,273		11,273		$ 10,204
PSU awards
Share-based Compensation
Total stock-based compensation expense	758	268	1,170	328
Total unamortized stock-based compensation expense	4,973		4,973		1,547
DSU awards
Share-based Compensation
Total stock-based compensation expense	257	$ 353	483	$ 511
Total unamortized stock-based compensation expense	568		568		$ 209
2021 ESPP
Share-based Compensation
Total stock-based compensation expense	$ 48		$ 143