Inventories (Details) - USD ($)	Oct. 31, 2016	Jul. 31, 2016
Inventory Disclosure [Abstract]
Raw materials and components	$ 55,306,000	$ 54,723,000
Work-in-process and finished goods	36,176,000	32,829,000
Total inventories	91,482,000	87,552,000
Less reserve for excess and obsolete inventories	15,823,000	16,198,000
Inventories, net	75,659,000	71,354,000
Inventory directly related to long-term contracts	2,745,000	2,896,000
Inventory related to contracts from third party commercial customers who outsource their manufacturing to us	$ 1,975,000	$ 1,428,000