Shareholders' Equity - Accounting for Share-based Compensation (Details) $ in Millions |
12 Months Ended |
|---|---|
|
Dec. 31, 2017
USD ($)
| |
| Equity [Abstract] | |
| Share-based payment award tax benefit | $ (236) |
| X | ||||||||||
- Definition Effective Income Tax Rate Reconciliation Share-based Compensation Excess Tax Benefit Amount No definition available.
|
| X | ||||||||||
- References No definition available.
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