Income Taxes - Deferred Taxes (Details) - USD ($)	Jul. 31, 2016	Jul. 31, 2015
Deferred tax assets:
Accrued expenses	$ 5,140,000	$ 3,650,000
Inventories	2,990,000	1,996,000
Accounts receivable	793,000	941,000
Other long-term liabilities	252,000	690,000
Stock-based compensation	3,665,000	2,640,000
Capital investment	546,000	546,000
Domestic NOLs		498,000
Foreign NOLs	5,154,000	4,861,000
Subtotal	18,540,000	15,822,000
Valuation allowance	(2,334,000)	(2,037,000)
Deferred tax assets, net of valuation allowance	16,206,000	13,785,000
Deferred tax liabilities
Property and equipment	(8,089,000)	(6,154,000)
Intangible assets	(19,818,000)	(14,711,000)
Goodwill	(11,878,000)	(10,409,000)
Deferred tax liabilities, gross	(39,785,000)	(31,274,000)
Net deferred tax liabilities	(23,579,000)	(17,489,000)
Reported in Consolidated Balance Sheets as:
Deferred income taxes - current asset		6,233,000
Deferred income taxes - noncurrent liability	(23,579,000)	(23,722,000)
Net deferred tax liabilities	$ (23,579,000)	$ (17,489,000)