Income Taxes - Schedule of Income Tax Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Income Tax Disclosure [Abstract]
Income tax expense	$ 220	$ 124
Reported income tax rate	20.90%	11.40%

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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MCKESSON CORP 10-Q