Property, plant, and equipment (Details) - Schedule of property, plant and equipment - USD ($) $ in Thousands	Jul. 31, 2016	Jul. 31, 2015
Schedule of property, plant and equipment [Abstract]
Building and building improvements	$ 4,915	$ 4,854
Machinery and equipment (includes asset under capital lease - see Note 9)	7,479	7,397
Office furniture and computer equipment	19,765	18,289
Leasehold improvements	5,172	4,958
	37,331	35,498
Accumulated depreciation and amortization	(29,829)	(28,262)
	7,502	7,236
Land and land improvements	712	712
	$ 8,214	$ 7,948