Income Taxes - Reconciliation of Potential Tax Benefits (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
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| Reconciliation of the beginning and ending amount of potential tax benefits | |||
| Beginning of year | $ 104 | $ 548 | $ 79 |
| Increases in prior year position | 4 | 41 | 0 |
| Increases in current year position | 17 | 13 | 470 |
| Decreases in prior year position | 0 | (474) | (1) |
| Settlements with taxing authorities | 0 | (24) | 0 |
| Lapse of statute of limitations | 0 | 0 | 0 |
| End of year | $ 125 | $ 104 | $ 548 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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