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Hedging Activities - Summary of Foreign Currency Gains and (Losses) from Non-Derivative Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	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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+ References

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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

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