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Debt (Schedule Of Outstanding Debt) (Details) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Instrument [Line Items] |  |
Current portion of long-term debt | $ 516 | $ 517
Short-term debt | 516 | 517
Long-term debt | 10,744 | 11,313
Long-term debt, net | 10,228 | 10,796
4.80% Senior Debt Obligations Due 2021 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 0 | 500
Interest rate | 4.80% |
2.75% Senior Debt Obligations Due 2022 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 500 | 499
Interest rate | 2.75% |
3.30% Senior Debt Obligations Due 2023 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 349 | 349
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 | $ 598 | 598
Interest rate | 3.50% |
3.875% Senior Debt Obligations Due 2024 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 996 | 995
Interest rate | 3.875% |
3.50% Senior Debt Obligations Due 2025 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 498 | 498
Interest rate | 3.50% |
1.349% Senior Debt Obligations Due 2026 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 647 | 677
Interest rate | 1.349% |
3.75% Senior Debt Obligations Due 2026 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 598 | 597
Interest rate | 3.75% |
4.375% Senior Debt Obligations Due 2029 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 1,499 | 1,499
Interest rate | 4.375% |
1.979% Senior Debt Obligations Due 2030 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 632 | 664
Interest rate | 1.979% |
2.250% Senior Debt Obligations Due 2030 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 738 | 737
Interest rate | 2.25% |
5.875% Senior Debt Obligations Due 2033 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 298 | 298
Interest rate | 5.875% |
4.75% Senior Debt Obligations Due 2039 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 495 | 495
Interest rate | 4.75% |
4.35% Senior Debt Obligation Due 2047 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 493 | 493
Interest rate | 4.35% |
4.20% Senior Debt Obligations Due 2048 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 592 | 592
Interest rate | 4.20% |
4.90% Senior Debt Obligations Due 2049 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 1,238 | 1,237
Interest rate | 4.90% |
5.70% Mortgage Due 2035 |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 320 | 331
Interest rate | 5.70% |
Other |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 4 | $ 5

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