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Equity-Based Compensation (Equity Based Awards - Settled in Cash) (Details) - USD ($) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Accrued equity based compensation | $ 23,900,000 |  | $ 18,200,000
Non Current Liabilities |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Accrued equity based compensation | 20,700,000 |  | $ 14,700,000
Management Stock Purchase Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share-based liabilities paid (in thousands) | $ 4,022,000 | $ 4,433,000 |
Management Stock Purchase Plan | Restricted stock units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Average company stock price measurement period | 200 days |  |
Restricted stock units credited (in shares) | $ 28,230 | $ 54,974 |

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- Definition Amount of cash paid to settle liability for award under share-based payment arrangement. + References 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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