Credit Facility - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified			1 Months Ended	3 Months Ended
	Jul. 28, 2012	Jul. 30, 2011	Apr. 29, 2011 Amended Credit Agreement Year	Jul. 28, 2012 Amended Credit Agreement	Jul. 28, 2012 2009 Credit Facility
Line of Credit Facility [Line Items]
Credit facility, borrowing capacity			$ 1,000,000
Credit facility maturity term, in years			5
Increase in commitments under credit agreement, maximum			300,000
Percentage of Loan Cap under Amended Credit Agreement			10.00%
Amount of Loan Cap under Amended Credit Agreement			50,000
Amortization of deferred financing fees				10,180	6,580
Unamortized deferred costs					16,341
Deferred financing amortization term				5 years
Line of credit facility, amount outstanding	302,800	509,600
Letters of credit, outstanding amount	$ 35,067	$ 31,214