New Accounting Pronouncements (Details) - USD ($) $ in Millions |
Jan. 01, 2019 |
Dec. 31, 2018 |
|---|---|---|
| New Accounting Pronouncements [Abstract] | ||
| New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets | $ 1,000 | |
| Reclassification of Capital Leases to Other Assets | $ 88 | |
| Reclassification of Capital Leases to Other Liabilities | $ 109 |