XML 107 R69.htm IDEA: XBRL DOCUMENT v3.10.0.1
Employee Stock-based Compensation Plans - Weighted-Average Fair Value and Total Fair Value of Shares Vested (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted-average fair value of restricted shares units granted (in usd per share) $ 37.98    
Restricted Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted-average fair value of restricted shares units granted (in usd per share) $ 37.98 $ 34.88 $ 26.61
Total fair value of shares vested (in millions) $ 53 $ 50 $ 61