Fair Value Measurements And Disclosure (Notional Amount Of Our Outstanding Derivative Positions) (Details) - USD ($) $ in Millions |
Jun. 30, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Derivative [Line Items] | ||
| Notional Amount of Outstanding Derivative Positions | $ 45,925 | $ 46,947 |
| Interest Rate Swaps [Member] | ||
| Derivative [Line Items] | ||
| Notional Amount of Outstanding Derivative Positions | 21 | 853 |
| Cross-Currency Swaps [Member] | ||
| Derivative [Line Items] | ||
| Notional Amount of Outstanding Derivative Positions | 45,606 | 42,325 |
| Interest Rate Locks [Member] | ||
| Derivative [Line Items] | ||
| Notional Amount of Outstanding Derivative Positions | 0 | 3,500 |
| Foreign Exchange Contracts [Member] | ||
| Derivative [Line Items] | ||
| Notional Amount of Outstanding Derivative Positions | $ 298 | $ 269 |