Inventories (Details) (USD $)	Apr. 30, 2012	Jul. 31, 2011
Raw materials and components	$ 58,217,000	$ 53,678,000
Work-in-process and finished goods	33,874,000	34,299,000
Total Inventories	92,091,000	87,977,000
Less reserve for excess and obsolete inventories	15,427,000	13,316,000
Inventories, net	76,664,000	74,661,000
Inventory directly related to long-term contracts	4,709,000	8,041,000
Inventory related to contracts from third party commercial customers who outsource their manufacturing to us	1,135,000	1,339,000
BFT-1 Program [Member]
Inventory directly related to long-term contracts	$ 3,140,000