Share-Based Compensation (Aggregate Intrinsic Value for Stock Options Outstanding and Exercisable) (Details) - USD ($) $ in Millions	Aug. 04, 2018	Jul. 29, 2017
Share-Based Compensation [Abstract]
Outstanding	$ 15	$ 23
Outstanding and exercisable	$ 13	$ 23

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant