v3.19.3.a.u2
Employee Benefit Plans - Stock unit activity (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Summary of stock unit activity      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number 17,172,815    
RSU Stock Settled [Member]      
Summary of stock unit activity      
Stock Units, Outstanding Beginning of year 7,546,973    
Stock Units, Granted 2,045,503    
Stock Units, Forfeited / Cancelled (99,748)    
Stock Units, Issued (3,269,682)    
Stock Units, Outstanding End of year 6,223,046 7,546,973  
Not Vested at End of Year 4,185,141    
Weighted-Average Grant-Date Fair Value, beginning of year $ 43.41    
Weighted-Average Grant-Date Fair Value, Granted 67.77    
Weighted-Average Grant-Date Fair Value, Forfeited / Cancelled 62.93    
Weighted-Average Grant-Date Fair Value, Issued 34.32    
Weighted-Average Grant-Date Fair Value, ending of year 55.99 $ 43.41  
Weighted-Average Grant-Date Fair Value Not Vested, ending of year $ 56.17    
Total Fair Value, Issued $ 225,000 $ 154,000 $ 159,000
Employee Benefit Plans Additional (Textual) [Abstract]      
Unrecognized compensation cost from stock options $ 93,000    
Weighted average period of recognition of unvested options, in months 1 year 8 months 15 days    
Longest weighted-average period of recognition of unvested options, in months 2 years 8 months 23 days    
Weighted-Average Grant-Date Fair Value, granted   $ 52.45 $ 48.77
Total Fair Value, Issued $ 225,000 $ 154,000 $ 159,000
RSU Cash Settled [Member]      
Summary of stock unit activity      
Stock Units, Outstanding Beginning of year 376,608    
Stock Units, Granted 319,552    
Stock Units, Forfeited / Cancelled (6,914)    
Stock Units, Issued (92,255)    
Stock Units, Outstanding End of year 596,991 376,608  
Not Vested at End of Year 153,457    
Weighted-Average Grant-Date Fair Value, beginning of year $ 62.21    
Weighted-Average Grant-Date Fair Value, Granted 68.20    
Weighted-Average Grant-Date Fair Value, Forfeited / Cancelled 61.35    
Weighted-Average Grant-Date Fair Value, Issued 61.61    
Weighted-Average Grant-Date Fair Value, ending of year 64.54 $ 62.21  
Weighted-Average Grant-Date Fair Value Not Vested, ending of year $ 64.54    
Total Fair Value, Issued $ 6,000 $ 1,000  
Employee Benefit Plans Additional (Textual) [Abstract]      
Unrecognized compensation cost from stock options $ 5,000    
Weighted average period of recognition of unvested options, in months 1 year 8 months 12 days    
Longest weighted-average period of recognition of unvested options, in months 2 years 1 month 13 days    
Weighted-Average Grant-Date Fair Value, granted   $ 53.68  
Total Fair Value, Issued $ 6,000 $ 1,000