Derivative Instruments and Hedging Activities, Pre-tax Effects of Derivative Instruments on AOCIL and Income (Details) - Interest Rate Swaps [Member] - Cash Flow Hedging [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	May 03, 2019	Apr. 27, 2018	May 03, 2019	Apr. 27, 2018	Aug. 03, 2018
Interest Rate Cash Flow Hedges [Abstract]
Amount of (loss) income recognized in AOCIL on derivatives (effective portion)			$ (6,629)		$ 13,103
Ineffectiveness recorded in earnings on interest rate cash flow hedge			0	$ 0
Interest Expense [Member]
Interest Rate Cash Flow Hedges [Abstract]
Amount of loss (gain) reclassified from AOCIL into income (effective portion)	$ (99)	$ 865	$ 43	$ 2,852