Condensed Consolidated Statement of Shareholder's Equity (unaudited) (Parenthetical) - Accumulated Other Comprehensive Loss (AOCI) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Fair value of effective portion of cash flow hedges, tax provision (benefit)	$ 0	$ (67)	$ (9)	$ (24)
Pension and other benefits, tax provision (benefit)	$ 0	$ (1)	$ (1)	$ (2)

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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