Stockholders' Equity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended	12 Months Ended
	Jun. 08, 2011	Feb. 03, 2013	Aug. 27, 2012	Jan. 29, 2012
Schedule Of Stockholders Equity [Line Items]
Stock split		Two-for-one stock split
Number of shares per share after stock split	2
Common stock shares authorized before stock split	200,000,000
Common stock, shares authorized	400,000,000	400,000,000		400,000,000
Special voting stock shares authorized before stock split	30,000,000
Special voting stock, authorized	60,000,000	60,000,000		60,000,000
Number of voting rights for the holders of special voting stock		One vote for each share held
Ratio of conversion of exchangeable shares		The exchangeable shares can be converted on a one for one basis by the holder at any time into common shares of the Company plus a cash payment for any accrued and unpaid dividends
Maturity period for conversion of exchangeable shares into common shares		July 26, 2047
Conversion of exchangeable shares into common shares		The Company has the right to convert the exchangeable shares into common shares of the Company at any time after the earlier of July 26, 2047, the date on which less than 4,188 exchangeable shares are outstanding or in the event of certain events such as a change in control
Purchased non-controlling interest			$ 26,013
Percentage of interest accounted			80.00%
Non-controlling interest, carrying amount			5,680	4,805
Purchase of non-controlling interest, decrease in equity		26,013
Additional Paid-In Capital [Member]
Schedule Of Stockholders Equity [Line Items]
Purchase of non-controlling interest, decrease in equity		$ 20,333