Supplemental Financial Statement Data (Schedule of Statements of Cash Flow) (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 28, 2019	Jul. 29, 2018	Jul. 30, 2017
Employee Benefits And Deferred Compensation Payments	$ (60)	$ (59)	$ (58)
Other Operating Activities, Cash Flow Statement	(4)	5	3
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities	(64)	(54)	(55)
Interest Paid, Including Capitalized Interest, Operating and Investing Activities	367	152	110
Interest Received	3	4	5
Income Taxes Paid, Net	117	128	320
Build-to-suit lease commitment	$ 20	$ 0	$ 0