NET INCOME (LOSS) PER SHARE - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Oct. 24, 2015	Oct. 25, 2014
Common Class A [Member]
Numerator:
Net income allocated, basic	$ 3,353	$ 2,912
Conversion of Class B to Class A shares	983	877
Effect of share-based compensation on allocated net income	3	2
Net income allocated, diluted	$ 4,339	$ 3,791
Denominator:
Weighted average shares outstanding, basic (in shares)	9,577	9,409
Conversion of Class B to Class A shares (in shares)	4,319	4,361
Dilutive effect of share-based compensation (in shares)	5	19
Weighted average shares outstanding, diluted (in shares)	13,901	13,789
Common Class B [Member]
Numerator:
Net income allocated, basic	$ 983	$ 877
Conversion of Class B to Class A shares	0	0
Effect of share-based compensation on allocated net income	0	0
Net income allocated, diluted	$ 983	$ 877
Denominator:
Weighted average shares outstanding, basic (in shares)	4,319	4,361
Conversion of Class B to Class A shares (in shares)	0	0
Dilutive effect of share-based compensation (in shares)	0	0
Weighted average shares outstanding, diluted (in shares)	4,319	4,361