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Debt (Outstanding Debt) (Details) - USD ($) $ in Millions | Sep. 30, 2024 | Jun. 30, 2024 | Feb. 29, 2024 | Dec. 31, 2023 | Sep. 30, 2023 | Mar. 31, 2023
--- | --- | --- | --- | --- | --- | ---
Debt Instrument [Line Items] |  |  |  |  |  |
Current portion of long-term debt | $ 518 |  |  | $ 1,619 |  |
Short-term debt | 518 |  |  | 1,619 |  |
Long-term debt | 12,848 |  |  | 13,463 |  |
Long-term debt, net | 12,330 |  |  | 11,844 |  |
Senior notes – 3.50% due 2024 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 0 |  |  | 600 |  |
Interest rate (as a percent) | 3.50% | 3.50% |  |  |  |
Senior notes – 3.875% due 2024 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 0 |  |  | 1,000 |  |
Interest rate (as a percent) | 3.875% |  |  |  |  |
Senior notes – 3.50% due 2025 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 500 |  |  | 499 |  |
Interest rate (as a percent) | 3.50% |  |  |  |  |
Senior notes – 1.349% due 2026 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 623 |  |  | 617 |  |
Interest rate (as a percent) | 1.349% |  |  |  |  |
Senior notes – 3.75% due 2026 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 599 |  |  | 599 |  |
Interest rate (as a percent) | 3.75% |  |  |  |  |
Senior notes – 4.375% due 2029 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 1,499 |  |  | 1,499 |  |
Interest rate (as a percent) | 4.375% |  |  |  |  |
Senior notes – 1.979% due 2030 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 603 |  |  | 601 |  |
Interest rate (as a percent) | 1.979% |  |  |  |  |
Senior notes – 2.25% due 2030 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 742 |  |  | 741 |  |
Interest rate (as a percent) | 2.25% |  |  |  |  |
Senior notes – 2.375% due 2031 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 397 |  |  | 397 |  |
Interest rate (as a percent) | 2.375% |  |  |  |  |
Senior notes – 5.750% due 2032 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 493 |  |  | 493 |  |
Interest rate (as a percent) | 5.75% |  |  |  |  |
Senior notes – 5.875% due 2033 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 298 |  |  | 298 |  |
Interest rate (as a percent) | 5.875% |  |  |  |  |
Senior notes – 5.400% due 2033 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 593 |  |  | 592 |  |
Interest rate (as a percent) | 5.40% |  |  |  | 5.40% |
Senior notes – 5.150% due 2034 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 495 |  |  | 0 |  |
Interest rate (as a percent) | 5.15% |  | 5.15% |  |  |
Senior notes – 4.75% due 2039 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 496 |  |  | 496 |  |
Interest rate (as a percent) | 4.75% |  |  |  |  |
Senior notes – 4.35% due 2047 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 494 |  |  | 494 |  |
Interest rate (as a percent) | 4.35% |  |  |  |  |
Senior notes – 4.20% due 2048 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 593 |  |  | 593 |  |
Interest rate (as a percent) | 4.20% |  |  |  |  |
Senior notes – 4.90% due 2049 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 1,239 |  |  | 1,239 |  |
Interest rate (as a percent) | 4.90% |  |  |  |  |
Senior notes – 2.90% due 2051 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 346 |  |  | 346 |  |
Interest rate (as a percent) | 2.90% |  |  |  |  |
Senior notes – 6.25% due 2052 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 491 |  |  | 491 |  |
Interest rate (as a percent) | 6.25% |  |  |  |  |
Senior notes – 5.450% due 2053 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 591 |  |  | 591 |  |
Interest rate (as a percent) | 5.45% |  |  |  |  | 5.45%
Senior notes – 5.700% due 2053 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 988 |  |  | 988 |  |
Interest rate (as a percent) | 5.70% |  |  |  | 5.70% |
Senior notes – 5.450% due 2054 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 493 |  |  | 0 |  |
Interest rate (as a percent) | 5.45% |  | 5.45% |  |  |
Mortgage – 5.70% due 2035 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 271 |  |  | 284 |  |
Interest rate (as a percent) | 5.70% |  |  |  |  |
Other |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt | $ 4 |  |  | $ 5 |  |

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