CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 242	$ 526	$ 42	$ 999
Other Comprehensive Income (Loss), Net of Tax
Foreign currency translation adjustments	43	(113)	55	(216)
Unrealized gains on cash flow hedges	8	35	33	37
Changes in retirement-related benefit plans	0	3	96	15
Other Comprehensive Income (Loss), Net of Tax	51	(75)	184	(164)
Comprehensive Income	293	451	226	835
Comprehensive Income Attributable to Noncontrolling Interests	(66)	(46)	(161)	(114)
Comprehensive Income Attributable to McKesson Corporation	$ 227	$ 405	$ 65	$ 721

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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