Inventories (Details) (USD $)	Jan. 31, 2015	Jul. 31, 2014
Raw materials and components	$ 53,236,000us-gaap_InventoryRawMaterials	$ 50,423,000us-gaap_InventoryRawMaterials
Work-in-process and finished goods	30,360,000	27,218,000
Total inventories	83,596,000us-gaap_InventoryGross	77,641,000us-gaap_InventoryGross
Less reserve for excess and obsolete inventories	16,124,000us-gaap_InventoryValuationReserves	16,309,000us-gaap_InventoryValuationReserves
Inventories, net	67,472,000us-gaap_InventoryNet	61,332,000us-gaap_InventoryNet
Inventory directly related to long-term contracts	4,139,000	1,000,000
Inventory related to contracts from third party commercial customers who outsource their manufacturing to us	517,000	654,000
ATIP Contract [Member]
Inventory directly related to long-term contracts	$ 1,728,000

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.

+ Details

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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

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

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-Publisher FASB

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- Definition

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

+ Details

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- Definition

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

-Publisher SEC

-Name Regulation S-X (SX)

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-Topic 210

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Section 09

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