Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Apr. 27, 2012	Apr. 29, 2011	Apr. 27, 2012	Apr. 29, 2011
Comprehensive Income [Abstract]
Net income	$ 18,974	$ 15,154	$ 68,385	$ 67,665
Other comprehensive income [Abstract]
Change in fair value of interest rate swaps, net of tax	4,540	2,329	10,902	11,905
Total comprehensive income	23,514	17,483	79,287	79,570
Tax benefit (expense) related to interest rate swaps	$ 1,808	$ 1,987	$ 2,000	$ 3,065

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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+ Details

- Definition

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

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+ Details

- Definition

Total tax effect of the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. The change includes an entity's share of an equity investee's increase or decrease in deferred hedging gains or losses. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References+ Details

- Definition

Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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