CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 3,722	$ 1,287	$ (4,340)
Other comprehensive income, net of tax
Foreign currency translation adjustments	674	60	184
Unrealized gains (losses) on cash flow and other hedges	(63)	14	(36)
Changes in retirement-related benefit plans	62	41	22
Other comprehensive income, net of tax	673	115	170
Comprehensive income (loss)	4,395	1,402	(4,170)
Comprehensive income attributable to noncontrolling interests	(206)	(172)	(146)
Comprehensive income (loss) attributable to McKesson Corporation	$ 4,189	$ 1,230	$ (4,316)