Quarterly report pursuant to Section 13 or 15(d)

Employee Benefits and Compensation Plans - Summary of Share Option Awards (Details)

v3.19.1
Employee Benefits and Compensation Plans - Summary of Share Option Awards (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]    
Options Outstanding, Weighted- Average Contractual Term 6 years 7 days 6 years 2 months 19 days
Options Outstanding, Aggregate Intrinsic Value $ 33,072 $ 13,946
Time Based Options    
Number of Share Option Awards    
Outstanding as of January 1, 2019 5,686,793  
Exercised (129,150)  
Forfeited and cancelled (27,000)  
Outstanding as of March 31, 2019 5,530,643 5,686,793
Weighted-Average Exercise Price    
Outstanding as of January 1, 2019 $ 50.65  
Exercised 38.40  
Forfeited and cancelled 57.03  
Outstanding as of March 31, 2019 $ 50.90 $ 50.65
Performance-Based Awards    
Number of Share Option Awards    
Outstanding as of January 1, 2019 410,499  
Exercised (54,695)  
Forfeited and cancelled (156,251)  
Outstanding as of March 31, 2019 199,553 410,499
Weighted-Average Exercise Price    
Outstanding as of January 1, 2019 $ 45.67  
Exercised 19.00  
Forfeited and cancelled 59.43  
Outstanding as of March 31, 2019 $ 42.21 $ 45.67
Market-Based Awards    
Number of Share Option Awards    
Outstanding as of January 1, 2019 208,333  
Exercised 0  
Forfeited and cancelled 0  
Outstanding as of March 31, 2019 208,333 208,333
Weighted-Average Exercise Price    
Outstanding as of January 1, 2019 $ 59.43  
Exercised 0.00  
Forfeited and cancelled 0.00  
Outstanding as of March 31, 2019 $ 59.43 $ 59.43