Derivative Instruments and Hedging Activities, Changes in AOCIL, Net of Tax, Related to Interest Rate Swaps (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 03, 2018	Jul. 28, 2017	Jul. 29, 2016
Changes in AOCIL, net of tax, related to interest rate swaps [Roll Forward]
Balance	$ 544,507	$ 526,443	$ 538,268
Other comprehensive income before reclassifications	11,274	12,082	(6,683)
Amounts reclassified from AOCIL into earnings	(2,360)	(2,571)	(3,332)
Other comprehensive income (loss), net of tax	8,914	9,511	(10,015)
Balance	581,781	544,507	526,443
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in AOCIL, net of tax, related to interest rate swaps [Roll Forward]
Balance	(4,229)	(13,740)	(3,725)
Balance	$ 4,685	$ (4,229)	$ (13,740)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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