Derivative Instruments and Hedging Activities, Amounts Reclassified out of AOCIL Related to Interest Rate Swaps (Details) - USD ($) $ in Thousands	3 Months Ended										12 Months Ended
	Jul. 27, 2018	[1]	Apr. 27, 2018	Jan. 26, 2018	Oct. 27, 2017	Jul. 28, 2017	[1]	Apr. 28, 2017	Jan. 27, 2017	Oct. 28, 2016	Aug. 03, 2018	Jul. 28, 2017	Jul. 29, 2016
Amounts Reclassified Out of AOCL Related to Interest Rate Swaps [Abstract]
Interest expense											$ (15,169)	$ (14,271)	$ (14,052)
Provision for income taxes											30,803	96,988	77,120
Net of tax	$ 61,354		$ 48,747	$ 91,139	$ 46,380	$ 53,893		$ 46,924	$ 52,727	$ 48,355	247,620	201,899	189,299
Interest Rate Swaps [Member] | Cash Flow Hedging [Member]
Amounts Reclassified Out of AOCL Related to Interest Rate Swaps [Abstract]
Ineffectiveness recorded in earnings on interest rate cash flow hedge											0	0
Loss on Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Amounts Reclassified Out of AOCL Related to Interest Rate Swaps [Abstract]
Provision for income taxes											1,038	1,592	2,063
Net of tax											(2,360)	(2,571)	(3,332)
Loss on Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Amounts Reclassified Out of AOCL Related to Interest Rate Swaps [Abstract]
Interest expense											$ (3,398)	$ (4,163)	$ (5,395)

[1] The Company's fourth quarter of fiscal 2018 consisted of 14 weeks.