Intangibles, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2017	Jul. 31, 2016
Amortized intangible assets:
Gross Carrying Amount	$ 106,408	$ 35,824
Accumulated Amortization	(30,470)	(24,063)
Intangibles, net	75,938	11,761
Covenants not to compete
Amortized intangible assets:
Gross Carrying Amount	1,702	1,702
Accumulated Amortization	(1,389)	(1,235)
Intangibles, net	$ 313	$ 467
Useful life of intangible assets	1 year	2 years
Supply contracts and customer relationships
Amortized intangible assets:
Gross Carrying Amount	$ 75,462	$ 26,471
Accumulated Amortization	(22,248)	(17,052)
Intangibles, net	$ 53,214	$ 9,419
Useful life of intangible assets	9 years	3 years
Trade names
Amortized intangible assets:
Gross Carrying Amount	$ 23,859	$ 5,163
Accumulated Amortization	(4,989)	(3,423)
Intangibles, net	$ 18,870	$ 1,740
Useful life of intangible assets	2 years	2 years
Licenses and databases
Amortized intangible assets:
Gross Carrying Amount	$ 5,385	$ 2,488
Accumulated Amortization	(1,844)	(2,353)
Intangibles, net	$ 3,541	$ 135
Useful life of intangible assets	3 years	1 year

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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