Goodwill And Other Intangible Assets (Narrative) (Details) (USD $)	9 Months Ended
Apr. 30, 2015	Jul. 31, 2014
Indefinite-lived Intangible Assets [Line Items]
Goodwill impairment	$ 0us-gaap_GoodwillImpairmentLoss
Intangible assets, net	36,002,000	36,045,000
Amortization of existing intangible assets	4,900,000us-gaap_AmortizationOfIntangibleAssets
Foreign exchange translation decrease of intangible assets	1,300,000
Northern Technical [Member]
Indefinite-lived Intangible Assets [Line Items]
Amount of intangibles acquired	$ 6,200,000

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit, from foreign currency translation and purchase accounting adjustments.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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