Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Jul. 31, 2016
Income Taxes [Line Items]
Discrete tax benefit		$ 200,000
U.S. Federal statutory tax rate	35.00%	35.00%
Income before income taxes	$ 3,511,000	$ 1,530,000
Unrecognized tax benefits, accrued interest and penalties	500,000		$ 400,000
Unrecognized tax benefits, for uncertain tax positions	7,500,000
Maximum
Income Taxes [Line Items]
Discrete tax benefit	$ 100,000