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

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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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Number of shares authorized for issuance under share-based payment arrangement.

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Share-Based Compensation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jul. 08, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized for issuance (in shares)					14,650,000
Shares of common stock reserved for issuance (in shares)					6,743,800
Compensation expense	$ 4.9	$ 0.7	$ 12.7	$ 1.7
RSUs and PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	28.6		$ 28.6
Weighted average period for recognition			3 years 1 month 6 days
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 0.1		$ 0.1
Weighted average period for recognition			2 years 1 month 6 days