Schedule of Intangible Assets Including Estimates of Assets Acquired (Detail) (USD $) In Millions, unless otherwise specified	Jan. 30, 2015	Jan. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 122	$ 163
Accumulated amortization	(98)	(84)
Net carrying value	24us-gaap_FiniteLivedIntangibleAssetsNet	79us-gaap_FiniteLivedIntangibleAssetsNet
Indefinite-lived intangible assets	13	14
Total intangible assets, Gross carrying value	135	177
Total intangible assets, Net carrying value	37	93
In-Process Research And Development
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	9	10
Trade Names
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	4	4
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	70	94
Accumulated amortization	(57)	(47)
Net carrying value	13	47
Software and Technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	52	65
Accumulated amortization	(41)	(36)
Net carrying value	11	29
Other
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	0	4
Accumulated amortization	0	(1)
Net carrying value	$ 0	$ 3

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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