Business Combinations (Fair Value Of Assets Acquired And Liabilities Assumed) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013	Feb. 22, 2013 PSS World Medical [Member] Amounts Previously Recognized as of Acquisition Date [Member]		Sep. 30, 2013 PSS World Medical [Member] Purchase Price Allocation Adjustments [Member]	Sep. 30, 2013 PSS World Medical [Member] Amounts Recognized as of Acquisition Date as Adjusted [Member]	Feb. 22, 2013 PSS World Medical [Member] Amounts Recognized as of Acquisition Date as Adjusted [Member]
Business Acquisition [Line Items]
Current assets, net of cash and cash equivalents acquired			$ 706	[1]	$ 5	$ 711
Goodwill	6,323	6,405	1,145	[1]	(12)	1,133
Intangible assets			557	[1]	11	568
Other long-term assets			183	[1]	0	183
Current liabilities			(376)	[1]	(4)	(380)
Current portion of long-term debt			(635)	[1]	0	(635)	(600)
Other long-term liabilities			(281)	[1]	0	(281)
Net assets acquired, less cash and cash equivalents			$ 1,299	[1]	$ 0	$ 1,299

[1] As previously reported in our Form 10-K for the year ended March 31, 2013.