Net Income (Loss) Per Share and Weighted Average Shares (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Apr. 30, 2021	Jan. 29, 2021	Oct. 30, 2020	May 01, 2020	Jan. 31, 2020	Nov. 01, 2019	Apr. 30, 2021	May 01, 2020
Net Income (Loss) Per Share and Weighted Average Shares [Abstract]
Net income (loss) per share numerator	$ 33,470	$ 14,000	$ 170,680	$ (161,932)	$ 61,168	$ 43,223	$ 218,150	$ (57,541)
Net income (loss) per share denominator [Abstract]
Weighted average shares (in shares)	23,725,185			23,777,916			23,718,777	23,922,360
Add potential dilution [Abstract]
Nonvested stock awards and units (in shares)	82,225			0			69,228	0
Diluted weighted average shares (in shares)	23,807,410			23,777,916			23,788,005	23,922,360