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Debt (Schedule Of Outstanding Debt) (Details) - USD ($) $ in Millions | Sep. 30, 2019 | Dec. 31, 2018 | Mar. 31, 2018
--- | --- | --- | ---
Debt Instrument [Line Items] |  |  |
Short-term: Commercial paper | $ 325 | $ 0 |
Current portion of long-term debt | 514 | 314 |
Short-term debt | 1,139 | 314 |
Long-term debt | 11,943 | 5,824 |
Long-term debt, net | 11,429 | 5,510 |
Term Loan Facility |  |  |
Debt Instrument [Line Items] |  |  |
Short-term: Term loan facility | 300 | 0 |
2.35% Senior Debt Obligations Due 2019 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 0 | 300 |
Interest rate | 2.35% |  |
2.35% Senior Debt Obligations Due 2020 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 500 | 499 |
Interest rate | 2.35% |  |
3.50% Senior Debt Obligations Due 2020 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 698 | 0 |
Interest rate | 3.50% |  |
4.80% Senior Debt Obligations Due 2021 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 499 | 499 |
Interest rate | 4.80% |  |
Floating Rate Senior Debt Obligations Due 2021 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 298 | 0 |
2.75% Senior Debt Obligations Due 2022 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 498 | 497 |
Interest rate | 2.75% |  |
3.30% Senior Debt Obligations Due 2023 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 348 | 348 |
Interest rate | 3.30% |  |
4.05% Senior Debt Obligations Due 2023 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 249 | 249 |
Interest rate | 4.05% |  |
3.50% Senior Debt Obligations Due 2024 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 597 | 597 |
Interest rate | 3.50% |  |
3.875% Senior Debt Obligations Due 2024 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 993 | 0 |
Interest rate | 3.875% |  |
3.50% Senior Debt Obligations Due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 497 | 496 |
Interest rate | 3.50% |  |
1.349% Senior Debt Obligations Due 2026 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 603 | 0 |
Interest rate | 1.349% |  |
3.75% Senior Debt Obligations Due 2026 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 597 | 596 |
Interest rate | 3.75% |  |
4.375% Senior Debt Obligations Due 2029 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 1,499 | 0 |
Interest rate | 4.375% |  |
1.979% Senior Debt Obligations Due 2030 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 602 | 0 |
Interest rate | 1.979% |  |
5.875% Senior Debt Obligations Due 2033 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 298 | 297 |
Interest rate | 5.875% |  |
4.75% Senior Debt Obligations Due 2039 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 494 | 0 |
Interest rate | 4.75% |  |
4.35% Senior Debt Obligation Due 2047 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 492 | 492 |
Interest rate | 4.35% |  |
4.20% Senior Debt Obligations Due 2048 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 592 | 592 |
Interest rate | 4.20% |  | 4.20%
4.90% Senior Debt Obligations Due 2049 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 1,237 | 0 |
Interest rate | 4.90% |  |
5.70% Mortgage Due 2035 |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 347 | 358 |
Interest rate | 5.70% |  |
Other |  |  |
Debt Instrument [Line Items] |  |  |
Long-term debt | $ 5 | $ 4 |

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