Stock-based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
Oct. 29, 2023	Oct. 30, 2022	Jul. 30, 2023
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		$ 0
Share-Based Payment Arrangement, Exercise of Option, Tax Benefit		0
Cash received from the exercise of stock options	$ 0	2
EPS Performance Restricted Stock Units [Member]
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Nonvested, Units	936
Nonvested, Weighted-Average Grant-Date Fair Value	$ 42.99
EPS Performance Restricted Stock Units [Member] \| Minimum [Member]
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
EPS Performance Restricted Stock Units [Member] \| Maximum [Member]
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Time Lapse, and EPS Performance Restricted Stock Units [Member]
Stock-based Compensation
Remaining unearned compensation on nonvested awards	$ 83
Weighted-average remaining service period, years	1 year 10 months 24 days
Nonvested, Units	3,008		2,274
Fair value of restricted units and shares vested	$ 30	$ 34
Granted, Weighted-Average Grant-Date Fair Value	$ 41.09	$ 47.12
Nonvested, Weighted-Average Grant-Date Fair Value	$ 43.26		$ 45.39
TSR Performance Restricted Stock/Units [Member]
Stock-based Compensation
Remaining unearned compensation on nonvested awards	$ 24
Weighted-average remaining service period, years	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	75.00%	100.00%
Nonvested, Units	936		948
Fair value of restricted units and shares vested	$ 12	$ 21
Granted, Weighted-Average Grant-Date Fair Value	$ 44.18	$ 53.74
Nonvested, Weighted-Average Grant-Date Fair Value	$ 47.40		$ 51.81

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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