Equity - Additional Information (Detail) (Stock Options)	3 Months Ended
May 04, 2013
Minimum
Equity [Line Items]
Share-based compensation arrangement, expiration date	Jun. 30, 2013
Maximum
Equity [Line Items]
Share-based compensation arrangement, expiration date	Apr. 30, 2023

Date the equity-based award expires, in CCYY-MM-DD format.

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)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardExpirationDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration