Inventories (Details) (USD $)	Apr. 30, 2015	Jul. 31, 2014
Inventory Disclosure [Abstract]
Raw materials and components	$ 52,438,000us-gaap_InventoryRawMaterials	$ 50,423,000us-gaap_InventoryRawMaterials
Work-in-process and finished goods	32,162,000	27,218,000
Total inventories	84,600,000us-gaap_InventoryGross	77,641,000us-gaap_InventoryGross
Less reserve for excess and obsolete inventories	16,348,000us-gaap_InventoryValuationReserves	16,309,000us-gaap_InventoryValuationReserves
Inventories, net	68,252,000us-gaap_InventoryNet	61,332,000us-gaap_InventoryNet
Inventory directly related to long-term contracts	2,964,000	1,000,000
Inventory related to contracts from third party commercial customers who outsource their manufacturing to us	$ 507,000	$ 654,000

Net carrying amount of Inventory directly related to long-term contracts.

No definition available.

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- Definition

Carrying amount as of the balance sheet date of inventories related to contracts from third-party commercial customers who outsource their manufacturing to the Company.

+ References

No definition available.

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- Definition

Amount before valuation reserves of merchandise or goods held by the entity that are readily available for sale and items held by the entity which are partially complete or in the process of being readied for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Number 210

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

+ References

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

+ Details

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- Definition

Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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- Definition

Amount of valuation reserve for inventory.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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