Useful Lives of Major Classes of Assets (Parenthetical) (Detail) (Maximum, Leasehold Improvements)	12 Months Ended
Jan. 31, 2015
Maximum \| Leasehold Improvements
Property, Plant and Equipment, Estimated Useful Lives, Lease Terms [Line Items]
Useful lives in asset class	10 years

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

No definition available.

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration