Customer and Geographic Information (Details) - USD ($)	3 Months Ended
Oct. 31, 2015	Oct. 31, 2014
Major customer
Revenues from External Customers
Minimum percentage of consolidated net sales sold to one customer or individual country requiring additional and separate disclosure	10.00%	10.00%
U.S. government
Revenues from External Customers
Percentage of revenue generated from external customer type	41.40%	24.90%
Commercial (United States)
Revenues from External Customers
Percentage of revenue generated from external customer type	14.60%	13.90%
Total United States
Revenues from External Customers
Percentage of revenue generated from external customer type	56.00%	38.80%
North African country
Revenues from External Customers
Percentage of revenue generated from external customer type	6.10%	14.60%
Other international
Revenues from External Customers
Percentage of revenue generated from external customer type	37.90%	46.60%
Total International
Revenues from External Customers
Percentage of revenue generated from external customer type	44.00%	61.20%
Revenue generated from external customers	$ 28,252,000	$ 46,756,000
U.S. Prime Contractor \| Major customer \| Sales Revenue, Net
Revenues from External Customers
Percentage of revenue generated from external customer type	0.00%	14.40%

Percentage of revenue generated from a single external customer type.

No definition available.

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- Definition

The minimum percentage of consolidated net sales that, if made to one customer or country, would require additional and separate disclosure.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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