Goodwill and Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2015	Jul. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (15,873)	$ (13,284)
Net intangibles	21,425us-gaap_FiniteLivedIntangibleAssetsNet	25,242us-gaap_FiniteLivedIntangibleAssetsNet
Covenants not to compete
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,750	2,939
Supply contracts & customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	27,829	27,986
Trade name
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	5,193	5,791
Licenses and databases
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 2,526	$ 1,810

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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