NET INCOME PER SHARE - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2022	Apr. 24, 2021	Apr. 30, 2022	Apr. 24, 2021
Class of Stock [Line Items]
Net (loss) income	$ (3,231)	$ 2,574	$ 14,227	$ 10,490
Distributed and allocated undistributed Net (loss) income to unvested restricted shareholders	(93)	82	429	336
Net (loss) income available to Class A and Class B shareholders	(3,138)	2,492	13,798	10,154
Numerator:
Net (loss) income allocated, basic	(3,138)	2,492	13,798	10,154
Common Class A
Class of Stock [Line Items]
Net (loss) income available to Class A and Class B shareholders	(2,447)	1,943	10,757	7,914
Numerator:
Net (loss) income allocated, basic	(2,447)	1,943	10,757	7,914
Conversion of Class B to Class A shares	(691)	551	3,041	2,242
Effect of share-based compensation on allocated net (loss) income	(19)		0
Net (loss) income allocated, diluted	$ (3,157)	$ 2,494	$ 13,798	$ 10,156
Denominator:
Weighted average shares outstanding, basic (in shares)	9,876	9,850	9,871	9,850
Conversion of Class B to Class A shares (in shares)	4,294	4,294	4,294	4,294
Weighted average shares outstanding, diluted (in shares)	14,170	14,144	14,165	14,144
Common Class B
Class of Stock [Line Items]
Net (loss) income available to Class A and Class B shareholders	$ (691)	$ 551	$ 3,041	$ 2,242
Numerator:
Net (loss) income allocated, basic	(691)	551	3,041	2,242
Conversion of Class B to Class A shares	0	0	0	0
Effect of share-based compensation on allocated net (loss) income	(14)		0
Net (loss) income allocated, diluted	$ (705)	$ 551	$ 3,041	$ 2,242
Denominator:
Weighted average shares outstanding, basic (in shares)	4,294	4,294	4,294	4,294
Conversion of Class B to Class A shares (in shares)	0	0	0	0
Weighted average shares outstanding, diluted (in shares)	4,294	4,294	4,294	4,294