Consolidated Statements of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Mar. 31, 2013
Income Statement [Abstract]
Revenues	$ 179,045	[1]	$ 137,392	[1]	$ 122,196	[1]
Cost of Sales	(167,634)		(129,040)		(115,315)
Gross Profit	11,411		8,352		6,881
Operating Expenses
Selling, distribution and administrative expenses	(7,901)		(5,388)		(4,110)
Research and development	(392)		(457)		(433)
Claims and litigation charges	(150)		(68)		(72)
Gain on business combination	0		0		81
Total Operating Expenses	(8,443)		(5,913)		(4,534)
Operating Income	2,968		2,439		2,347
Other Income, Net	63		32		34
Impairment of an Equity Investment	0		0		(191)
Interest Expense	(374)		(300)		(240)
Total income from continuing operations before income taxes	2,657		2,171		1,950
Income Tax Expense	(815)		(757)		(587)
Income from continuing operations	1,842		1,414		1,363
Income (Loss) from Discontinued Operations, Net of Tax	(299)		(156)		(25)
Net Income	1,543		1,258		1,338
Net loss attributable to noncontrolling interests	(67)		5		0
Net Income Attributable to McKesson	$ 1,476		$ 1,263		$ 1,338
Diluted
Continuing operations	$ 7.54	[2]	$ 6.08	[2]	$ 5.69	[2]
Discontinued operations	$ (1.27)	[2]	$ (0.67)	[2]	$ (0.10)	[2]
Total	$ 6.27	[2]	$ 5.41	[2]	$ 5.59	[2]
Basic
Continuing operations	$ 7.66	[2]	$ 6.19	[2]	$ 5.81	[2]
Discontinued operations	$ (1.29)	[2]	$ (0.68)	[2]	$ (0.10)	[2]
Total	$ 6.37	[2]	$ 5.51	[2]	$ 5.71	[2]
Weighted Average Common Shares
Diluted	235		233		239
Basic	232		229		235

[1] Net revenues were attributed to geographic areas based on the customers’ shipment locations.

[2] Certain computations may reflect rounding adjustments.