Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	Oct. 31, 2015	Jul. 31, 2015
Amortized intangibles:
Accumulated amortization	$ (20,347)	$ (18,967)
Net intangibles	16,229	17,857
Covenants not to compete [Member]
Amortized intangibles:
Gross carrying amount	1,670	1,691
Supply contracts & customer relationships [Member]
Amortized intangibles:
Gross carrying amount	27,282	27,506
Trade names [Member]
Amortized intangibles:
Gross carrying amount	5,133	5,129
Licenses and databases [Member]
Amortized intangibles:
Gross carrying amount	$ 2,491	$ 2,498

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

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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