Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Income (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amounts reclassified from accumulated other comprehensive income (loss)	$ (56)	$ 14	$ (72)	$ 25
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amounts reclassified from accumulated other comprehensive income (loss)	$ (56)	$ 14	$ (72)	$ 25

Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Period Type:	duration