Commitments and Contingent Liabilities - Additional Information (Detail) - USD ($)		9 Months Ended
	Apr. 28, 2016	Jul. 30, 2016	Aug. 01, 2015
Commitments And Contingencies [Line Items]
Percentage of joint venture loan guaranteed by company		50.00%
Guarantee obligations note payable principal amount		$ 5,000,000
Guarantee obligations maximum limit of note payable principal amount for maturity		$ 750,000
Guarantee obligations principal balance of pool of loans percentage		80.00%
Percentage of collateral value for pool of loan securing note		100.00%
Distribution from joint venture		$ 1,000,005	$ 500,000
Guarantee obligations outstanding note payable principal amount		1,010,067
Collateral value for pool of loan securing note payable by joint venture		$ 1,847,205
Majestic 21 [Member]
Commitments And Contingencies [Line Items]
Percentage of ownership interest		50.00%
Distribution from joint venture	$ 1,000,005