Accumulated Other Comprehensive Income (Loss) (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jan. 28, 2018	Jan. 29, 2017	Jan. 28, 2018	Jan. 29, 2017	Jul. 30, 2017	Jul. 31, 2016
Beginning Balance				$ (53)
Other comprehensive income (loss), after tax		$ 63	$ (6)	31	$ (8)
Ending Balance		(21)		(21)
Accumulated Other Comprehensive Income Foreign Currency Translation Tax (Benefit) Expense		6	6	6	6	$ 6	$ 6
Accumulated Other Comprehensive Income Cashflow Hedges Tax (Benefit) Expense		(8)	(10)	(8)	(10)	(12)	(23)
Accumulated Other Comprehensive Income Unamortized Pension And Post Retirement Tax (Benefit) Expense		25	30	25	30	$ 30	$ 35
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Beginning Balance	[1]			(84)	(124)
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				35	(25)
Reclassification from AOCI, Current Period, Net of Tax				0	0
Other comprehensive income (loss), after tax				35	(25)
Ending Balance	[1]	(49)	(149)	(49)	(149)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Beginning Balance	[2]			(22)	(41)
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				7	19
Reclassification from AOCI, Current Period, Net of Tax				1	5
Other comprehensive income (loss), after tax				8	24
Ending Balance	[2]	(14)	(17)	(14)	(17)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Beginning Balance	[3]			53	61
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				(2)	0
Reclassification from AOCI, Current Period, Net of Tax				(9)	(8)
Other comprehensive income (loss), after tax				(11)	(8)
Ending Balance	[3]	42	53	42	53
AOCI Attributable to Parent [Member]
Beginning Balance				(53)	(104)
Other Comprehensive Income (Loss) Before Reclassifications Net Of Tax				40	(6)
Reclassification from AOCI, Current Period, Net of Tax				(8)	(3)
Other comprehensive income (loss), after tax				32	(9)
Ending Balance		$ (21)	$ (113)	$ (21)	$ (113)

[1] Included a tax expense of $6 as of January 28, 2018, July 30, 2017, January 29, 2017, and July 31, 2016.

[2] Included a tax benefit of $8 as of January 28, 2018, $12 as of July 30, 2017, $10 as of January 29, 2017, and $23 as of July 31, 2016.

[3] Included a tax expense of $25 as of January 28, 2018, $30 as of July 30, 2017, and January 29, 2017, and $35 as of July 31, 2016.