SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Net Income Per Share (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Jul. 25, 2015 USD ($) class_common_stock $ / shares shares	Jul. 26, 2014 USD ($) $ / shares shares	Jul. 27, 2013 USD ($) $ / shares shares
Accounting Policies [Abstract]
Number of common stock classes | class_common_stock	2
Common stock cash dividends, percent Class A is entitled greater than Class B	54.00%
Class A Common Stock
Numerator:
Net income allocated, basic	$ 23,050	$ 3,788	$ 18,089
Conversion of Class B to Class A shares	6,885	1,141	7,053
Effect of share-based compensation on allocated net income	46	(20)	6
Net income allocated, diluted	$ 29,981	$ 4,909	$ 25,148
Denominator:
Weighted average shares outstanding, basic (in shares) | shares	9,459	9,258	8,297
Conversion of Class B to Class A shares (in shares) | shares	4,353	4,374	5,197
Dilutive effect of share-based compensation (in shares) | shares	48	62	112
Weighted average shares outstanding, diluted (in shares) | shares	13,860	13,694	13,606
Net income per share
Basic (in dollars per share) | $ / shares	$ 2.44	$ 0.41	$ 2.18
Diluted (in dollars per share) | $ / shares	$ 2.16	$ 0.36	$ 1.85
Class B Common Stock
Numerator:
Net income allocated, basic	$ 6,885	$ 1,141	$ 7,053
Conversion of Class B to Class A shares	0	0	0
Effect of share-based compensation on allocated net income	(23)	(11)	(5)
Net income allocated, diluted	$ 6,862	$ 1,130	$ 7,048
Denominator:
Weighted average shares outstanding, basic (in shares) | shares	4,353	4,374	5,197
Conversion of Class B to Class A shares (in shares) | shares	0	0	0
Dilutive effect of share-based compensation (in shares) | shares	0	0	0
Weighted average shares outstanding, diluted (in shares) | shares	4,353	4,374	5,197
Net income per share
Basic (in dollars per share) | $ / shares	$ 1.58	$ 0.26	$ 1.36
Diluted (in dollars per share) | $ / shares	$ 1.58	$ 0.26	$ 1.36