Investments (Investments Portfolio and AFS Continuous Unrealized Loss Position) (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
Investment Holdings [Line Items]
Cost method, equity method, and other investments, cost	$ 503				$ 503				$ 652
Cost method, equity method, and other investments, fair value	503				503				652
Short-term and long-term investments, cost	8,103				8,103				6,986
Short-term and long-term investments, unrealized gains	220				220				228
Short-term and long-term investments, unrealized losses	(72)				(72)				(52)
Short-term and long-term investments, fair value	8,251				8,251				7,162
AFS Continuous Unrealized Loss Position
Less than 12 months, fair value	834				834				758
Less than 12 months, unrealized losses	(24)				(24)				(4)
More than 12 months, fair value	210				210				228
More than 12 months, unrealized losses	(46)				(46)				(48)
AFS OTTI Losses
OTTI losses recognized in OCI	1		1		3		13
OTTI losses recognized in earnings	1		1		2		5
Total OTTI losses recognized	2		1		5		18
Corporate Debt Securities
Investment Holdings [Line Items]
Available-for-sale securities, cost	2,912				2,912				1,947
Available-for-sale securities, unrealized gains	38				38				20
Available-for-sale securities, unrealized losses	(10)				(10)				(6)
Available-for-sale securities, fair value	2,940				2,940				1,961
AFS Continuous Unrealized Loss Position
Less than 12 months, fair value	608				608				256
Less than 12 months, unrealized losses	(7)				(7)				(1)
More than 12 months, fair value	11				11				16
More than 12 months, unrealized losses	(3)				(3)				(5)
Auction Rate Securities
Investment Holdings [Line Items]
Available-for-sale securities, cost	167				167				167
Available-for-sale securities, unrealized gains	0				0				0
Available-for-sale securities, unrealized losses	(34)				(34)				(34)
Available-for-sale securities, fair value	133				133				133
AFS Continuous Unrealized Loss Position
Less than 12 months, fair value	0				0				0
Less than 12 months, unrealized losses	0				0				0
More than 12 months, fair value	133				133				133
More than 12 months, unrealized losses	(34)				(34)				(34)
Mortgage Backed Securities
Investment Holdings [Line Items]
Available-for-sale securities, cost	786				786				783
Available-for-sale securities, unrealized gains	9				9				10
Available-for-sale securities, unrealized losses	(11)				(11)				(8)
Available-for-sale securities, fair value	784				784				785
AFS Continuous Unrealized Loss Position
Less than 12 months, fair value	208				208				161
Less than 12 months, unrealized losses	(3)				(3)				(1)
More than 12 months, fair value	57				57				67
More than 12 months, unrealized losses	(8)				(8)				(7)
US Government Agencies Debt Securities
Investment Holdings [Line Items]
Available-for-sale securities, cost	2,972				2,972				2,731
Available-for-sale securities, unrealized gains	43				43				26
Available-for-sale securities, unrealized losses	0				0				(1)
Available-for-sale securities, fair value	3,015				3,015				2,756
AFS Continuous Unrealized Loss Position
Less than 12 months, fair value									267
Less than 12 months, unrealized losses	0				0				(1)
More than 12 months, fair value	0				0				0
More than 12 months, unrealized losses	0				0				0
Foreign Government Debt Securities
Investment Holdings [Line Items]
Available-for-sale securities, cost	56				56				130
Available-for-sale securities, unrealized gains	0				0				1
Available-for-sale securities, unrealized losses	0				0				0
Available-for-sale securities, fair value	56				56				131
Certificates of Deposit
Investment Holdings [Line Items]
Available-for-sale securities, cost	73				73				119
Available-for-sale securities, unrealized gains	0				0				0
Available-for-sale securities, unrealized losses	0				0				0
Available-for-sale securities, fair value	73				73				119
Other Asset-backed Securities
Investment Holdings [Line Items]
Available-for-sale securities, cost	474				474				351
Available-for-sale securities, unrealized gains	2				2				1
Available-for-sale securities, unrealized losses	(1)				(1)				(3)
Available-for-sale securities, fair value	475				475				349
AFS Continuous Unrealized Loss Position
Less than 12 months, fair value	0				0				74
Less than 12 months, unrealized losses	0				0				(1)
More than 12 months, fair value	9				9				12
More than 12 months, unrealized losses	(1)				(1)				(2)
Marketable Equity Securities
Investment Holdings [Line Items]
Available-for-sale securities, cost	115				115				73
Available-for-sale securities, unrealized gains	127				127				164
Available-for-sale securities, unrealized losses	(14)				(14)				0
Available-for-sale securities, fair value	228				228				237
AFS Continuous Unrealized Loss Position
Less than 12 months, fair value	18				18
Less than 12 months, unrealized losses	(14)				(14)
More than 12 months, fair value	0				0
More than 12 months, unrealized losses	0				0
Exchange Traded Funds
Investment Holdings [Line Items]
Trading securities, cost	45				45				33
Trading securities, unrealized gains	1				1				6
Trading securities, unrealized losses	(2)				(2)
Trading securities, fair value	44				44				39
Debt Securities
AFS Gross Realized Gain (Loss)
Proceeds from sales	1,486	[1]	1,297	[1]	4,453	[1]	4,090	[1]
Gross realized gains	21	[1]	7	[1]	45	[1]	24	[1]
Gross realized losses	(6)	[1]	(4)	[1]	(13)	[1]	(11)	[1]
Impairment losses recognized	(1)	[1]	0	[1]	(2)	[1]	(5)	[1]
Equity Securities
AFS Gross Realized Gain (Loss)
Proceeds from sales	28	[2]	0	[2],[3]	81	[2],[4]	0	[2],[3]
Gross realized gains	17	[2]	85	[2],[3]	72	[2],[4]	85	[2],[3]
Gross realized losses	0	[2]	0	[2],[3]	0	[2],[4]	0	[2],[3]
Impairment losses recognized	$ 0	[2]	$ (10)	[2],[3]	$ (4)	[2],[4]	$ (15)	[2],[3]

[1] (a) Includes available-for-sale debt securities.

[2] (b) Includes marketable equity securities, cost method, equity method, exchange-traded funds, and other investments.

[3] (d) As a result of the Ardian acquisition that occurred during the three months ended January 28, 2011, the Company recognized an $85 million non-cash gain on its previously held minority investment.

[4] (c) As a result of the Salient and PEAK acquisitions, the Company recognized a non-cash gain of $38 million during the nine months ended January 27, 2012 on its previously held minority investments.