Fair Value Measurements (Fair Value Measurement Of Assets And Liabilities) (Details) - Measured On Recurring Basis [Member] - USD ($) $ in Millions		Jul. 28, 2024	Jul. 30, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value		$ 12	$ 21
Total liabilities at fair value		117	97
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value		1	12
Total liabilities at fair value		102	94
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value		6	7
Total liabilities at fair value		15	3
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value		5	2
Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[1]	2	0
Derivatives liabilities at fair value	[1]	0	1
Foreign Exchange Contract [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[1]	2	0
Derivatives liabilities at fair value	[1]	0	1
Commodity Derivative Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[2]	6	16
Derivatives liabilities at fair value	[2]	16	5
Commodity Derivative Contracts [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[2]	0	11
Derivatives liabilities at fair value	[2]	1	3
Commodity Derivative Contracts [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[2]	1	3
Derivatives liabilities at fair value	[2]	15	2
Commodity Derivative Contracts [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[2]	5	2
Equity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[3]	3	4
Equity Contract [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets at fair value	[3]	3	4
Deferred Compensation Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	[4]	1	1
Deferred Compensation Investment [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments at fair value	[4]	1	1
Deferred Compensation Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation obligation	[4]	101	91
Deferred Compensation Obligation [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation obligation	[4]	$ 101	$ 91

[1] Based on observable market transactions of spot currency rates and forward rates.

[2] Level 1 and 2 are based on quoted futures exchanges and on observable prices of futures and options transactions in the marketplace. Level 3 is based on unobservable inputs in which there is little or no market data, which requires management’s own assumptions within an internally developed model.

[3] Based on equity index swap rates.

[4] Based on the fair value of the participants’ investments.