Shareholders' Equity - Stock Options - Additional Information (Detail) - shares	9 Months Ended
Oct. 31, 2015	Nov. 01, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Shares exercised	0	0

Number of share options (or share units) exercised during the current period.

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

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Name:	us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration