XML 116 R98.htm IDEA: XBRL DOCUMENT v3.20.4
Equity - Restricted stock units (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Other disclosures        
Share-based payments subject to redemption $ 30 $ 31 $ 37 $ 36
Restricted stock units (RSUs) | Employee        
Share-based compensation        
Vesting terms 3 years      
Service period over which compensation expense would be amortized 1 year      
Restricted stock unit activity        
Non-vested at the beginning of the period (in shares) 339      
Granted (in shares) 196      
Vested (in shares) (94)      
Cancelled (in shares) (23)      
Non-vested at the end of the period (in shares) 418 339    
Weighted-average fair value per share        
Non-vested at the beginning of the period (in dollars per share) $ 108.02      
Granted (in dollars per share) 87.01      
Vested (in dollars per share) 117.33      
Cancelled (in dollars per share) 101.72      
Non-vested at the end of the period (in dollars per share) $ 96.45 $ 108.02    
Other disclosures        
Fair value of awards vested during the year $ 17 $ 16 $ 15  
Unrecognized compensation cost $ 23      
Weighted-average period for amortization of unrecognized compensation cost 1 year 9 months 18 days      
Share-based payments subject to redemption $ 23 $ 23