Stock-Based Compensation - RSUs to be Settled in Cash (Details) - Restricted Stock Units to be Settled in Cash - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to RSUs to be settled in cash	$ 8.4	$ 2.7
Payments to settle liabilities under compensation plan	7.9	$ 3.5
Accrued liabilities under compensation plan	$ 7.6		$ 8.7

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

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Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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