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Hedging Activities - Summary of Foreign Currency Gains and (Losses) from Non-Derivative Instruments (Details) - USD ($) $ in Millions | 12 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023
Derivatives designated for hedge accounting: | Net Investment Hedges | Euro Denominated Notes |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Euro-denominated notes | $ 0 | $ 0 | $ 7

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- Definition Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from derivative designated and qualifying as net investment hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4CCC -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4CCC + Details
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