CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ (677)	$ 553	$ (200)	$ 473
Other Comprehensive Income (Loss), Net of Tax
Foreign currency translation adjustments	(32)	26	12	(103)
Unrealized gains on cash flow hedges	13	2	25	2
Changes in retirement-related benefit plans	75	4	96	12
Other Comprehensive Income (Loss), Net of Tax	56	32	133	(89)
Comprehensive Income (Loss)	(621)	585	(67)	384
Comprehensive Income Attributable to Noncontrolling Interests	(35)	(47)	(95)	(68)
Comprehensive Income (Loss) Attributable to McKesson Corporation	$ (656)	$ 538	$ (162)	$ 316

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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