Restructuring Charges (Schedule of Pre-Tax Charges and Remaining Costs 2014 Iniative) (Details) (2014 Initiatives [Member], Severance Pay And Benefits [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Oct. 27, 2013
2014 Initiatives [Member] | Severance Pay And Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Accrued Balance at beginning of period	$ 0
Restructuring and Related Cost, Incurred Cost	20
Payments for Restructuring	0
Accrued Balance at end of period	$ 20