Intangibles, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2016	Jul. 31, 2015
Amortized intangible assets:
Gross Carrying Amount	$ 35,824	$ 36,824
Accumulated Amortization	(24,063)	(18,967)
Intangibles, net	11,761	17,857
Covenants not to compete
Amortized intangible assets:
Gross Carrying Amount	1,702	1,691
Accumulated Amortization	(1,235)	(900)
Intangibles, net	$ 467	$ 791
Useful life of intangible assets	2 years	3 years
Supply contracts and customer relationships
Amortized intangible assets:
Gross Carrying Amount	$ 26,471	$ 27,506
Accumulated Amortization	(17,052)	(13,551)
Intangibles, net	$ 9,419	$ 13,955
Useful life of intangible assets	3 years	4 years
Trade names
Amortized intangible assets:
Gross Carrying Amount	$ 5,163	$ 5,129
Accumulated Amortization	(3,423)	(2,467)
Intangibles, net	$ 1,740	$ 2,662
Useful life of intangible assets	2 years	3 years
Licenses and databases
Amortized intangible assets:
Gross Carrying Amount	$ 2,488	$ 2,498
Accumulated Amortization	(2,353)	(2,049)
Intangibles, net	$ 135	$ 449
Useful life of intangible assets	1 year	2 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=66006027&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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