CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Revenues	$ 55,679	$ 55,728
Cost of sales	(52,979)	(52,941)
Gross profit	2,700	2,787
Operating expenses	(1,966)	(2,130)
Restructuring, impairment and related charges	(56)	(23)
Total operating expenses	(2,022)	(2,153)
Operating income	678	634
Other income, net	27	37
Equity earnings and charges from investment in Change Healthcare Joint Venture	0	4
Interest expense	(60)	(56)
Income from continuing operations before income taxes	645	619
Income tax expense	(150)	(136)
Income from continuing operations	495	483
Loss from discontinued operations, net of tax	(1)	(6)
Net income	494	477
Net income attributable to noncontrolling interests	(50)	(54)
Net income attributable to McKesson Corporation	$ 444	$ 423
Diluted
Continuing operations (in dollars per share)	$ 2.72	$ 2.27
Discontinued operations (in dollars per share)	0	(0.03)
Total (in dollars per share)	2.72	2.24
Basic
Continuing operations (in dollars per share)	2.74	2.28
Discontinued operations (in dollars per share)	0	(0.03)
Total (in dollars per share)	$ 2.74	$ 2.25
Weighted-average common shares outstanding
Diluted (in shares)	163	189
Basic (in shares)	162	188