Financial Instruments (Offsetting Assets and Liabilities) (Details) - USD ($) $ in Millions	Jan. 31, 2021	Aug. 02, 2020
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Derivative Asset, Fair Value, Gross Asset	$ 20	$ 12
Derivative, Collateral, Obligation to Return Securities or Cash	0	(4)
Derivative Asset, Fair Value, Amount Offset Against Collateral	20	8
Derivative Liability, Fair Value, Gross Liability	6	11
Derivative, Collateral, Right to Reclaim Securities or Cash	0	(4)
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 6	$ 7

Derivative, Collateral, Obligation to Return Securities or Cash

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- Definition

Derivative, Collateral, Right to Reclaim Securities or Cash

+ References

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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Fair value, after effects of master netting arrangements, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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