Derivative Instruments and Hedging Activities, Changes in AOCIL, Net of Tax, Related to Interest Rate Swaps (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 02, 2019	Aug. 03, 2018	Jul. 28, 2017
Changes in AOCIL, net of tax, related to interest rate swaps [Roll Forward]
Balance	$ 581,781	$ 544,507	$ 526,443
Other comprehensive income (loss) before reclassifications	(11,752)	11,274	12,082
Amounts reclassified from AOCIL into earnings	154	(2,360)	(2,571)
Other comprehensive income (loss), net of tax	(11,598)	8,914	9,511
Balance	604,710	581,781	544,507
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in AOCIL, net of tax, related to interest rate swaps [Roll Forward]
Balance	4,685	(4,229)	(13,740)
Other comprehensive income (loss), net of tax	(11,598)	8,914	9,511
Balance	$ (6,913)	$ 4,685	$ (4,229)

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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