Supplemental Financial Statement Data (Schedule Of Balance Sheets - Plant Assets) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 31, 2011		Aug. 01, 2010		Aug. 02, 2009
Land	$ 64		$ 61
Buildings	1,224		1,182
Machinery and equipment	3,896		3,651
Projects in progress	179		149
Total cost	5,363		5,043
Accumulated depreciation	(3,260)	[1]	(2,992)	[1]
Plant assets	2,103		2,051		1,977
Depreciation expense	$ 265		$ 251		$ 264
Buildings [Member]
Property, plant and equipment minimum useful life	7
Property, plant and equipment maximum useful life	45
Machinery And Equipment [Member]
Property, plant and equipment minimum useful life	2
Property, plant and equipment maximum useful life	20

[1] Depreciation expense was $265 in 2011, $251 in 2010, and $264 in 2009. Buildings are depreciated over periods ranging from 7 to 45 years. Machinery and equipment are depreciated over periods generally ranging from 2 to 20 years.