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Stock-based Compensation - Time-Based RSUs (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Weighted-average grant date fair value per unit:      
Compensation expense recorded during the year $ 37,794 $ 45,105 $ 24,771
Time-based RSUs      
Stock-Based Compensation      
Percentage of the award vesting at each of the three anniversaries 33.00%    
Summary of equity award grants, RSUs      
Balance at beginning of year (in units) 587,000 642,000 627,000
Granted (in units) 173,000 311,000 334,000
Vested (in units) (312,000) (357,000) (300,000)
Forfeited or canceled (in units) (14,000) (9,000) (19,000)
Balance at end of year (in units) 434,000 587,000 642,000
Weighted-average grant date fair value per unit:      
Outstanding at beginning of year (in dollars per share) $ 29.37 $ 22.40 $ 20.39
Granted (in dollars per share) 58.90 34.98 22.88
Vested (in dollars per share) 28.08 21.75 18.73
Forfeited (in dollars per share) 39.48 28.14 22.29
Outstanding at end of year (in dollars per share) $ 41.74 $ 29.37 $ 22.40
Compensation expense recorded during the year $ 10,184 $ 9,515 $ 6,659
Unamortized compensation cost $ 4,912    
Number of shares expected to vest (in units) 401,000    
Weighted average remaining vesting period (in months) 8 months    
Time-based RSUs | Minimum      
Stock-Based Compensation      
Turnover rates (as a percent) 0    
Time-based RSUs | Maximum      
Stock-Based Compensation      
Turnover rates (as a percent) 20.3    
Time-based RSUs | Common Class A [Member]      
Stock-Based Compensation      
Number of share awarded for each RSU (in shares) 1