Intangibles, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2015	Jul. 31, 2014
Amortized intangible assets:
Gross Carrying Amount	$ 36,824	$ 38,526
Accumulated Amortization	(18,967)	(13,284)
Intangibles, net	17,857	25,242
Covenants not to compete
Amortized intangible assets:
Gross Carrying Amount	1,691	1,797
Accumulated Amortization	(900)	(615)
Intangibles, net	$ 791	$ 1,182
Useful life of intangible assets	3 years	4 years
Supply contracts & customer relationships
Amortized intangible assets:
Gross Carrying Amount	$ 27,506	$ 29,128
Accumulated Amortization	(13,551)	(9,747)
Intangibles, net	$ 13,955	$ 19,381
Useful life of intangible assets	4 years	5 years
Trade name
Amortized intangible assets:
Gross Carrying Amount	$ 5,129	$ 5,791
Accumulated Amortization	(2,467)	(1,479)
Intangibles, net	$ 2,662	$ 4,312
Useful life of intangible assets	3 years	4 years
Licenses and databases
Amortized intangible assets:
Gross Carrying Amount	$ 2,498	$ 1,810
Accumulated Amortization	(2,049)	(1,443)
Intangibles, net	$ 449	$ 367
Useful life of intangible assets	2 years	3 years

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- References

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