Intangibles, Net (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jul. 31, 2013	Jul. 31, 2012
Amortized intangible assets:
Gross Carrying Amount	$ 52,530	$ 38,444
Accumulated Amortization	(34,824)	(30,459)
Intangibles, net	17,706	7,985
Covenants not to compete
Amortized intangible assets:
Gross Carrying Amount	12,515	11,087
Accumulated Amortization	(10,965)	(10,685)
Intangibles, net	1,550	402
Weighted Average Remaining Useful Life (in years)	4 years	4 years
Supply contracts
Amortized intangible assets:
Gross Carrying Amount	26,322	26,041
Accumulated Amortization	(21,757)	(18,762)
Intangibles, net	4,565	7,279
Weighted Average Remaining Useful Life (in years)	8 years	6 years
Customer relationships
Amortized intangible assets:
Gross Carrying Amount	7,389
Accumulated Amortization	(395)
Intangibles, net	6,994
Weighted Average Remaining Useful Life (in years)	6 years
Trade name
Amortized intangible assets:
Gross Carrying Amount	2,998
Accumulated Amortization	(402)
Intangibles, net	2,596
Weighted Average Remaining Useful Life (in years)	4 years
Licenses and databases
Amortized intangible assets:
Gross Carrying Amount	3,306	1,316
Accumulated Amortization	(1,305)	(1,012)
Intangibles, net	$ 2,001	$ 304
Weighted Average Remaining Useful Life (in years)	3 years	1 year

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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- 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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- Definition

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.

+ References

No definition available.

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