Discontinued Operations Income Statement (Balance Sheet and Addtitional Disclosure) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Jul. 28, 2013	Apr. 28, 2013	Jan. 27, 2013	Oct. 28, 2012	Jul. 29, 2012	Apr. 29, 2012	Jan. 29, 2012	Oct. 30, 2011	Jul. 28, 2013	Jul. 29, 2012	Jul. 31, 2011
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operation, Revenue									$ 532	$ 532	$ 576
Discontinued Operation, Operating Income (Loss)									(331)	57	68
Discontinued Operation, Tax Effect of Discontinued Operation									100	(17)	(15)
Earnings (loss) from discontinued operations	(275)	12	19	13	1	8	16	15	(231)	40	53
Cash balance of discontinued operations - end of period	68								68
Disposal Group, Including Discontinued Operation, Accounts Receivable	54								54
Disposal Group, Including Discontinued Operation, Inventories	68								68
Disposal Group, Including Discontinued Operation, Prepaid Expenses	3								3
Current assets held for sale	193				0				193	0
Disposal Group, Including Discontinued Operation, Plant Assets	98								98
Disposal Group, Including Discontinued Operation, Goodwill	110								110
Disposal Group, Including Discontinued Operation, Intangible Assets, Net	150								150
Disposal Group, Including Discontinued Operation, Other Assets	35								35
Noncurrent assets held for sale	393				0				393	0
Disposal Group, Including Discontinued Operation, Accounts Payable	60								60
Disposal Group, Including Discontinued Operation, Accrued Liabilities	54								54
Current liabilities held for sale	114				0				114	0
Disposal Group, Including Discontinued Operation, Pension Plan Benefit Obligation	11								11
Disposal Group, Including Discontinued Operation, Other Liabilities	11								11
Noncurrent liabilities held for sale	$ 22				$ 0				$ 22	$ 0