Goodwill and Intangible Assets (Schedule of Intangible Assets Including Estimates of Assets Acquired) (Detail) (USD $) In Millions, unless otherwise specified	Oct. 31, 2014	Jan. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 122	$ 163
Accumulated amortization	(96)	(84)
Net carrying value	26	79
Indefinite-lived intangible assets	13	14
Total intangible asset, gross	135	177
Total intangible assets, Net carrying value	39	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	(56)	(47)
Net carrying value	14	47
Software and Technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	52	65
Accumulated amortization	(40)	(36)
Net carrying value	12	29
Other
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	0	4
Accumulated amortization	0	(1)
Net carrying value	$ 0	$ 3