Segment Information (Schedule of Segment Information) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2014		Jun. 30, 2013
Segment Reporting Information [Line Items]
Segment Reporting Revenue From External Customers	$ 44,058		$ 32,239
Operating Income	688		655
Interest Expense	(101)		(59)
Income from Continuing Operations Before Income Taxes	607		602
North America pharmaceutical distribution and services [Member]
Segment Reporting Information [Line Items]
Segment Reporting Revenue From External Customers	34,304	[1]	30,046	[1]
International pharmaceutical distribution and services [Member]
Segment Reporting Information [Line Items]
Segment Reporting Revenue From External Customers	7,607	[1]	0	[1]
Distribution Solutions [Member]
Segment Reporting Information [Line Items]
Segment Reporting Revenue From External Customers	43,290	[1]	31,403	[1]
Operating Income	748		619
Medical-Surgical distribution & services [Member]
Segment Reporting Information [Line Items]
Segment Reporting Revenue From External Customers	1,379	[1]	1,357	[1]
Technology Solutions [Member]
Segment Reporting Information [Line Items]
Segment Reporting Revenue From External Customers	768		836
Operating Income	68	[2]	127	[2]
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating Income	816		746
Corporate [Member]
Segment Reporting Information [Line Items]
Corporate Expenses, Net	$ (108)		$ (85)

[1] Revenues derived from services represent less than 2% of this segment’s total revenues.

[2] perating profit for the quarter ended June 30, 2014 includes a charge of $34 million related to the retained workforce business within our International Technology business.