Stock-Based Compensation - RSUs and PSUs to be Settled in Common Stock (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock compensation expense	$ 23,923	$ 21,980	$ 42,610	$ 36,892
Restricted Stock Units to be Settled in Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of restricted stock, vested			115,100	45,900
Non-cash stock compensation expense			31,600	$ 26,200
Unrecognized compensation cost, related to unvested RSUs to be settled in common stock, total	$ 116,000		$ 116,000
Expected weighted average period to recognize compensation cost on RSUs to be settled in common stock			2 years 4 months 20 days

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

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-Publisher FASB
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-Topic 718
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-Section 50
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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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Amount of noncash expense for share-based payment arrangement.

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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.

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