Fair Value Measurements - Recurring (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 29, 2016	Oct. 28, 2017	Jan. 28, 2017
Level 3 \| Auction rate securities
Liabilities
Proceeds from Sale of Other Assets	$ 2
Fair Value, Measurements, Recurring [Member] \| Level 1 \| Money market funds
Assets
Cash and cash equivalents	97	$ 84	$ 290
Other current assets	3	8	7
Fair Value, Measurements, Recurring [Member] \| Level 1 \| Marketable securities that fund deferred compensation
Assets
Other assets	96	98	96
Fair Value, Measurements, Recurring [Member] \| Level 2 \| Time deposits
Assets
Cash and cash equivalents	11	0	15
Short-term investments	1,527	1,649	1,332
Other current assets	100	100	100
Fair Value, Measurements, Recurring [Member] \| Level 2 \| Commercial paper
Assets
Short-term investments	250	588	349
Other current assets	60	60	60
Fair Value, Measurements, Recurring [Member] \| Level 2 \| Foreign currency derivative instruments
Assets
Other current assets	5	5	2
Liabilities
Accrued liabilities	3	5	3
Fair Value, Measurements, Recurring [Member] \| Level 2 \| Interest rate swap derivative instruments
Assets
Other current assets	0	3	0
Other assets	13	0	13
Liabilities
Long-term liabilities	$ 0	$ 3	$ 0

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Fair value portion of accrued expenses.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
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Fair value portion of other assets.

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Fair value portion of other liabilities.

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Amount of cash inflow from the sale of other assets as part of operating activities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 230
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