Share-Based Compensation Plans - Stock Option Narrative (Details) - USD ($) $ / shares in Units, $ in Millions |
9 Months Ended | |
---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
|
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
Closing share price (in dollars per share) | $ 112.49 | |
Aggregate intrinsic value of options outstanding | $ 39 | |
Unamortized deferred compensation expense | $ 416 | |
Remaining weighted-average amortization period (in years) | 2 years 1 month 6 days | |
Share options [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
Weighted average remaining contractual life (in years) | 2 years 2 months 12 days | 2 years 7 months 6 days |