Accumulated Other Comprehensive Income (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Apr. 27, 2014		Apr. 28, 2013	Apr. 27, 2014		Apr. 28, 2013	Jul. 28, 2013
Beginning Balance				$ (565)
Other comprehensive income (loss), after tax	90		(9)	38		67
Ending Balance	(527)			(527)
Accumulated Other Comprehensive Income Foreign Currency Translation Tax (Benefit) Expense	7			7			9
Accumulated Other Comprehensive Income Cashflow Hedges Tax (Benefit) Expense	1			1			3
Accumulated Other Comprehensive Income Unamortized Pension And Post Retirement Tax (Benefit) Expense	(392)			(392)			(424)
Accumulated Translation Adjustment [Member]
Beginning Balance				170	[1]
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				(2)
Other Comprehensive Income Reclassifications Current Period Net of Tax				(19)
Other comprehensive income (loss), after tax				(21)
Ending Balance	149	[1]		149	[1]
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Beginning Balance				5	[2]
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				(2)
Other Comprehensive Income Reclassifications Current Period Net of Tax				1
Other comprehensive income (loss), after tax				(1)
Ending Balance	4	[2]		4	[2]
Accumulated Defined Benefit Plans Adjustment [Member]
Beginning Balance				(740)	[3]
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				5
Other Comprehensive Income Reclassifications Current Period Net of Tax				55
Other comprehensive income (loss), after tax				60
Ending Balance	(680)	[3]		(680)	[3]
Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance				(565)
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				1
Other Comprehensive Income Reclassifications Current Period Net of Tax				37
Other comprehensive income (loss), after tax				38		67
Ending Balance	(527)			(527)
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	(18)		0	(18)		0
Defined Benefit Plan Recognized Net Gain (Loss) Due to Settlements Net Of Tax				$ (11)

[1] Included a tax expense of $7 as of April 27, 2014, and $9 as of July 28, 2013. The amount reclassified from other comprehensive income was related to the divestiture of the European simple meals business

[2] Included a tax expense of $1 as of April 27, 2014, and $3 as of July 28, 2013.

[3] Included a tax benefit of $392 as of April 27, 2014, and $424 as of July 28, 2013. The amount reclassified from other comprehensive income included a pre-tax settlement charge of $18, or $11 after tax.