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Equity-Based Compensation - Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Options (Details) - Employee Stock Option [Member]
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Expected life (years) 3 years 8 months 12 days 3 years 10 months 24 days 4 years 2 months 12 days
Dividend yield 0.00% 0.00% 4.80%
Risk-free interest rate 2.40% 1.90% 1.20%
Expected volatility 34.90% 35.80% 36.20%