Stock-Based Compensation (Time-Lapse Restricted Stock Units, EPS Performance Restricted Stock Units And Strategic Performance Restricted Stock Units And TSR Performance Restricted Stock Units) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Jul. 29, 2012	Jul. 31, 2011	Aug. 01, 2010
Time Lapse, EPS And Strategic Performance Restricted Stock Units [Member]
Stock-Based Compensation
Nonvested at beginning of period, Units	2,710
Granted, Units	2,639
Vested, Units	(1,162)
Forfeited, Units	(236)
Nonvested at end of period, Units	3,951	2,710
Nonvested at beginning of period, Weighted-Average Grant-Date Fair Value	$ 35.11
Granted, Weighted-Average Grant-Date Fair Value	$ 32.38	$ 35.64	$ 32.25
Vested, Weighted-Average Grant-Date Fair Value	$ 35.73
Forfeited, Weighted Average Grant Date Fair Value	$ 33.28
Nonvested at end of period, Weighted-Average Grant-Date Fair Value	$ 33.19	$ 35.11
TSR Performance Restricted Stock/Units [Member]
Stock-Based Compensation
Nonvested at beginning of period, Units	3,431
Granted, Units	0
Vested, Units	0
Forfeited, Units	(1,288)
Nonvested at end of period, Units	2,143	3,431
Nonvested at beginning of period, Weighted-Average Grant-Date Fair Value	$ 40.78
Granted, Weighted-Average Grant-Date Fair Value	$ 0	$ 43.18	$ 33.84
Vested, Weighted-Average Grant-Date Fair Value	$ 0
Forfeited, Weighted Average Grant Date Fair Value	$ 45.50
Nonvested at end of period, Weighted-Average Grant-Date Fair Value	$ 37.94	$ 40.78