Property Plant and Equipment (Details) (USD $)	12 Months Ended
Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 115,370,000	$ 112,434,000
Less accumulated depreciation and amortization	95,037,000	89,602,000
Property, plant and equipment, net	20,333,000	22,832,000
Depreciation and amortization	7,837,000	10,205,000	14,253,000
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	103,812,000	101,272,000
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 11,558,000	$ 11,162,000

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

Gross amount of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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- Definition

Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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