CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Revenues	$ 47,899	$ 46,484	$ 144,206	$ 134,120
Cost of Sales	(45,027)	(43,586)	(135,642)	(125,626)
Gross Profit	2,872	2,898	8,564	8,494
Operating Expenses	(1,952)	(2,098)	(5,759)	(6,226)
Operating Income	920	800	2,805	2,268
Other Income, Net	13	12	43	53
Interest Expense	(87)	(93)	(267)	(284)
Income from Continuing Operations Before Income Taxes	846	719	2,581	2,037
Income Tax Expense	(204)	(198)	(704)	(606)
Income from Continuing Operations	642	521	1,877	1,431
Income (Loss) from Discontinued Operations, Net of Tax	5	(10)	(11)	(32)
Net Income	647	511	1,866	1,399
Net Income Attributable to Noncontrolling Interests	(13)	(39)	(39)	(55)
Net Income Attributable to McKesson Corporation	$ 634	$ 472	$ 1,827	$ 1,344
Diluted
Continuing operations (in dollars per share)	$ 2.71	$ 2.04	$ 7.86	$ 5.85
Discontinued operations (in dollars per share)	0.02	(0.04)	(0.05)	(0.13)
Total (in dollars per share)	2.73	2.00	7.81	5.72
Basic
Continuing operations (in dollars per share)	2.74	2.07	7.95	5.94
Discontinued operations (in dollars per share)	0.02	(0.04)	(0.04)	(0.14)
Total (in dollars per share)	2.76	2.03	7.91	5.80
Dividends declared per common share (in dollars per share)	$ 0.28	$ 0.24	$ 0.80	$ 0.72
Weighted Average Common Shares
Diluted (in shares)	232	236	234	235
Basic (in shares)	230	232	231	232