Stock Based Compensation - Unrecognized Compensation Cost (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation	$ 61.6
Weighted-average amortization period (in years)	1 year 4 months 24 days
Restricted stock and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation	$ 49.6
Weighted-average amortization period (in years)	2 years 4 months 24 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation	$ 6.7
Weighted-average amortization period (in years)	6 months
Incentive units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation	$ 5.3
Weighted-average amortization period (in years)	6 months

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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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