Goodwill and Other Intangible Assets, Net (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Jan. 24, 2014	Jan. 25, 2013	Jan. 24, 2014	Jan. 25, 2013	Apr. 26, 2013
The changes in the carrying amount of goodwill
Beginning balance			$ 10,329
Goodwill as a result of acquisitions			264
Goodwill, Purchase Accounting Adjustments			5
Currency adjustments, net			(5)
Ending balance	10,593		10,593
Balance of intangible assets, excluding goodwill
Intangible Assets, Gross (Excluding Goodwill)	4,666		4,666		4,771
Accumulated amortization	(2,294)		(2,294)		(2,098)
Carrying value	2,242		2,242
Intangible Assets, Net (Excluding Goodwill)	2,372		2,372		2,673
Amortization expense	89	88	263	247
Estimated aggregate amortization expense
Remaining 2014	87		87
2015	338		338
2016	326		326
2017	304		304
2018	288		288
2019	243		243
Thereafter	656		656
Purchased Technology and Patents
Balance of intangible assets, excluding goodwill
Original cost	3,944		3,944		3,896
Accumulated amortization	(1,883)		(1,883)		(1,702)
Carrying value	2,061		2,061		2,194
Trademarks and Tradenames
Balance of intangible assets, excluding goodwill
Original cost	408		408		408
Accumulated amortization	(329)		(329)		(320)
Carrying value	79		79		88
Other
Balance of intangible assets, excluding goodwill
Original cost	184		184		104
Accumulated amortization	(82)		(82)		(76)
Carrying value	102		102		28
Cardiac and Vascular Group
The changes in the carrying amount of goodwill
Beginning balance			2,624
Goodwill as a result of acquisitions			264
Goodwill, Purchase Accounting Adjustments			0
Currency adjustments, net			(13)
Ending balance	2,875		2,875
Restorative Therapies Group
The changes in the carrying amount of goodwill
Beginning balance			6,361
Goodwill as a result of acquisitions			0
Goodwill, Purchase Accounting Adjustments			5
Currency adjustments, net			8
Ending balance	6,374		6,374
Diabetes Group [Member]
The changes in the carrying amount of goodwill
Beginning balance			1,344
Goodwill as a result of acquisitions			0
Goodwill, Purchase Accounting Adjustments			0
Currency adjustments, net			0
Ending balance	1,344		1,344
In Process Research and Development [Member]
Balance of intangible assets, excluding goodwill
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 130		$ 130		$ 363