Derivative Instruments and Hedging Activities, Changes in AOCIL, Net of Tax, Related to Interest Rate Swaps (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2020	Aug. 02, 2019	Aug. 03, 2018
Changes in AOCIL, net of tax, related to interest rate swaps [Roll Forward]
Balance	$ 604,710	$ 581,781	$ 544,507
Other comprehensive income (loss) before reclassifications	(12,559)	(11,752)	11,274
Amounts reclassified from AOCIL into earnings	(874)	154	(2,360)
Other comprehensive income (loss), net of tax	(13,433)	(11,598)	8,914
Balance	418,389	604,710	581,781
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in AOCIL, net of tax, related to interest rate swaps [Roll Forward]
Balance	(6,913)	4,685	(4,229)
Other comprehensive income (loss), net of tax	(13,433)	(11,598)	8,914
Balance	$ (20,346)	$ (6,913)	$ 4,685

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

No definition available.

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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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