Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 718
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Percentage of vesting of share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Stock-based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Oct. 29, 2017	Oct. 30, 2016	Jan. 28, 2018	Jan. 29, 2017	Jul. 30, 2017
Stock-based Compensation
Proceeds from Stock Options Exercised			$ 0	$ 2
Excess Tax Benefit from Share-based Compensation, Operating Activities			$ 4	$ 6
EPS Performance Restricted Stock Units [Member]
Stock-based Compensation
Nonvested, Units			150
Nonvested, Weighted-Average Grant-Date Fair Value			$ 49.58
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			100.00%
Strategic Performance Restricted Stock Units [Member]
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		35.00%
Employee Stock Option [Member]
Stock-based Compensation
Remaining unearned compensation on nonvested awards			$ 3
Weighted-average remaining service period, years			1 year 1 month
Time Lapse E P S And Strategic Performance Restricted Stock Units [Member]
Stock-based Compensation
Remaining unearned compensation on nonvested awards			$ 34
Weighted-average remaining service period, years			1 year 9 months
Nonvested, Units			1,236		1,221
Nonvested, Weighted-Average Grant-Date Fair Value			$ 49.91		$ 50.86
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			689
Granted, Weighted-Average Grant-Date Fair Value			$ 46.95	$ 54.73
Fair value of restricted units and shares vested			$ 30	$ 51
TSR Performance Restricted Stock/Units [Member]
Stock-based Compensation
Remaining unearned compensation on nonvested awards			$ 38
Weighted-average remaining service period, years			2 years
Nonvested, Units			1,832		1,774
Nonvested, Weighted-Average Grant-Date Fair Value			$ 46.29		$ 48.24
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	125.00%	75.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			943
Granted, Weighted-Average Grant-Date Fair Value			$ 39.39	$ 39.53
Fair value of restricted units and shares vested			$ 38	$ 14
T S R Performance Restricted Stock Units Additional Shares [Member]
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	160
Financial [Member] \| Special Performance Restricted Stock Units [Member]
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		0.00%
Milestones [Member] \| Special Performance Restricted Stock Units [Member]
Stock-based Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		100.00%