Equity-Based Compensation - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Jan. 01, 2019
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of stock options exercised	$ 4.2
Aggregate intrinsic value of stock options outstanding	5.6
Aggregate intrinsic value of stock options exercisable	5.6
Restricted common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate Intrinsic value of stock unvested	2.2
Unrecognized equity based compensation	$ 0.5
Weighted average remaining vesting term	3 months 18 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate Intrinsic value of stock unvested	$ 877.1
Unrecognized equity based compensation	$ 686.2
Weighted average remaining vesting term	1 year 4 months 24 days
Intrinsic value of stock vested	$ 290.5
2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	8,603,066
Number of shares available for future grant (in shares)		6,202,378

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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