CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jan. 30, 2015	Jan. 31, 2014	Jan. 30, 2015	Jan. 31, 2014
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net income	$ 47,163us-gaap_NetIncomeLoss	$ 37,055us-gaap_NetIncomeLoss	$ 81,187us-gaap_NetIncomeLoss	$ 64,215us-gaap_NetIncomeLoss
Other comprehensive income (loss) before income tax (benefit) expense:
Change in fair value of interest rate swaps	(6,112)	1,505	(6,887)	1,377
Income tax (benefit) expense	(2,357)us-gaap_OtherComprehensiveIncomeLossTax	580us-gaap_OtherComprehensiveIncomeLossTax	(2,656)us-gaap_OtherComprehensiveIncomeLossTax	530us-gaap_OtherComprehensiveIncomeLossTax
Other comprehensive income (loss), net of tax	(3,755)	925	(4,231)	847
Comprehensive income	$ 43,408us-gaap_ComprehensiveIncomeNetOfTax	$ 37,980us-gaap_ComprehensiveIncomeNetOfTax	$ 76,956us-gaap_ComprehensiveIncomeNetOfTax	$ 65,062us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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