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v3.25.1

Debt and Financing Activities - Long-Term Debt (Details) - USD ($) $ in Millions |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 10, 2024 | Feb. 15, 2024 | Jun. 16, 2023 | Jun. 15, 2023 | Mar. 15, 2023 | Feb. 15, 2023 | Dec. 15, 2022 | Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt outstanding |  |  |  |  |  |  |  | $ 5,700 | $ 5,600 |
Current portion of long-term debt |  |  |  |  |  |  |  | 1,191 | 50 |
Retired and redeemed outstanding principal amount |  |  |  |  |  |  |  | 519 | 288 | $ 1,274
Purchase of U.S. government obligations for the satisfaction and discharge of long-term debt |  |  |  |  |  |  |  | $ 0 | 647 | $ 0
Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Redemption price (percent) | 101.00% |  |  | 101.00% |  |  |  |  |  |
Loans payable | Minimum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt instrument, redemption period (in days) | 10 days |  |  | 10 days |  |  |  |  |  |
Loans payable | Maximum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt instrument, redemption period (in days) | 60 days |  |  | 60 days |  |  |  |  |  |
4.25% Notes Due September 15, 2029 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) | 4.25% |  |  |  |  |  |  | 4.25% |  |
Aggregate principal amount | $ 500 |  |  |  |  |  |  |  |  |
Proceeds from issuance, net | $ 496 |  |  |  |  |  |  |  |  |
5.25% Notes due February 15, 2026 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) | 5.25% |  |  |  |  |  |  |  |  |
5.25% Notes due February 15, 2026 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) |  |  |  |  |  |  |  | 5.25% |  |
Retired and redeemed outstanding principal amount | $ 500 |  |  |  |  |  |  |  |  |
Redemption price (percent) | 100.00% |  |  |  |  |  |  |  |  |
4.90% Notes Due July 15, 2028 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) |  |  |  | 4.90% |  |  |  | 4.90% |  |
Aggregate principal amount |  |  |  | $ 400 |  |  |  |  |  |
Proceeds from issuance, net |  |  |  | $ 397 |  |  |  |  |  |
5.10% Notes Due July 15, 2033 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) |  |  |  | 5.10% |  |  |  | 5.10% |  |
Aggregate principal amount |  |  |  | $ 600 |  |  |  |  |  |
Proceeds from issuance, net |  |  |  | $ 592 |  |  |  |  |  |
3.80% Notes Due March 15, 2024 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) |  |  |  | 3.80% |  |  |  |  |  |
Retired and redeemed outstanding principal amount |  |  | $ 268 |  |  |  |  |  |  |
Redemption price (percent) |  |  | 98.75% |  |  |  |  |  |  |
Debt Instrument, repurchased face amount |  |  | $ 271 |  |  |  |  |  |  |
Purchase of U.S. government obligations for the satisfaction and discharge of long-term debt |  |  | $ 647 |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  |  |  |  |  | $ 9 |
5.25% Notes Due 2026 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) |  |  |  |  |  | 5.25% |  |  |  |
Aggregate principal amount |  |  |  |  |  | $ 500 |  |  |  |
Proceeds from issuance, net |  |  |  |  |  | $ 497 |  |  |  |
Redemption price (percent) |  | 100.00% |  |  |  |  |  |  |  |
2.85% Notes Due March 15, 2023 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) |  |  |  |  | 2.85% |  |  |  |  |
Retired and redeemed outstanding principal amount |  |  |  |  | $ 360 |  |  |  |  |
2.70% Notes Due December 15, 2022 | Loans payable |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate on debt instruments (percent) |  |  |  |  |  |  | 2.70% |  |  |
Retired and redeemed outstanding principal amount |  |  |  |  |  |  | $ 400 |  |  |

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