Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended
	Jan. 25, 2013	Jan. 27, 2012	Jan. 25, 2013	Jan. 27, 2012	Apr. 27, 2012	Jan. 27, 2012 Physio-Control	Jan. 30, 2012 Physio-Control
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net assets	$ 17,836		$ 17,836		$ 17,113		$ 164
Proceeds from divestiture of Physio-Control							386
Summary of Operating Results from Discontinued Operations before Tax
Net sales		112		323
Earnings from operations of Physio-Control		23		48
Physio-Control divestiture-related costs		(12)		(24)
Income tax expense		(5)		(9)
Deferred income tax benefit on sale	0	84	0	84
Earnings from discontinued operations	0	90	0	99
Reclassification of divestiture related costs from continuing operations to discontinued operations						$ 12