Goodwill and Other Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Jan. 27, 2012	Jan. 28, 2011	Jan. 27, 2012	Jan. 28, 2011	Apr. 29, 2011
The changes in the carrying amount of goodwill
Balance as of			$ 9,520
Goodwill as a result of acquisitions			399
Purchase accounting adjustments, net	9		38
Currency adjustments, net			(42)
Balance as of	9,915		9,915
Balance of intangible assets, excluding goodwill
Original cost	4,498		4,498		4,369
Accumulated amortization	(1,785)		(1,785)		(1,644)
Carrying value	2,713		2,713		2,725
Estimated aggregate amortization expense
Remaining 2012			83
2013			319
2014			310
2015			293
2016			281
Thereafter			1,058
Total estimated amortization expense			2,344
Amortization expense	84	86	255	252
Purchased Technology and Patents
Balance of intangible assets, excluding goodwill
Original cost	3,609		3,609		3,509
Accumulated amortization	(1,378)		(1,378)		(1,261)
Carrying value	2,231		2,231		2,248
Trademarks and Tradenames
Balance of intangible assets, excluding goodwill
Original cost	373		373		373
Accumulated amortization	(306)		(306)		(290)
Carrying value	67		67		83
Acquired in Process Research and Development
Balance of intangible assets, excluding goodwill
Original cost	369		369		338
Accumulated amortization	0		0		0
Carrying value	369		369		338
Other Intangible Assets
Balance of intangible assets, excluding goodwill
Original cost	147		147		149
Accumulated amortization	(101)		(101)		(93)
Carrying value	46		46		56
Cardiac and Vascular Group
The changes in the carrying amount of goodwill
Balance as of			2,662
Goodwill as a result of acquisitions			0
Purchase accounting adjustments, net			6
Currency adjustments, net			(40)
Balance as of	2,628		2,628
Restorative Therapies Group
The changes in the carrying amount of goodwill
Balance as of			6,858
Goodwill as a result of acquisitions			399
Purchase accounting adjustments, net			32
Currency adjustments, net			(2)
Balance as of	$ 7,287		$ 7,287