Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Income (Loss) (Schecule of amounts reclassified from AOCI) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Apr. 28, 2013		Apr. 29, 2012		Apr. 28, 2013		Apr. 29, 2012
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax [Abstract]
Reclassification adjustment for (gains) losses included in net earnings, before tax			$ (6)		$ 1		$ 2
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, [Abstract]
Reclassification of prior service credit included in net earnings, before tax					(2)	[1]	(1)	[1]
Reclassification of net actuarial loss included in net earnings before tax	31	[1]	21	[1]	93	[1]	62	[1]
Total Pension and Other Postretirement Benefit amortization included in net earnings, before Tax	31		21		91		61
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax Effect [Abstract]
Reclassification adjustment for (gains) losses included in net earnings, tax (expense) benefit			2
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax [Abstract]
Total Pension and Other Postretirement Benefit amortization included in net earnings, tax expense (benefit)	(11)		(7)		(32)		(22)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract]
Reclassification adjustment for (gains) losses included in net earnings, after-tax			(4)		1		2
Pension and other postretirement liability adjustments, after-tax [Abstract]
Total Pension and Other Postretirement Benefit amortization included in net earnings, net of tax	20		14		59		39
Foreign Exchange Contract [Member] | Cost Of Products Sold [Member]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax [Abstract]
Reclassification adjustment for (gains) losses included in net earnings, before tax	(1)		(6)		(2)
Interest Rate Swap [Member] | Interest Expense [Member]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax [Abstract]
Reclassification adjustment for (gains) losses included in net earnings, before tax	$ 1				$ 3		$ 2

[1] These items are included in the components of net periodic benefit costs (see Note 10 for additional details).