Goodwill and Intangible Assets - Components of Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 33,331	$ 33,367
Less accumulated amortization	(23,489)	(21,559)
Intangible assets, net	9,842	11,808
Covenants Not-to-Compete [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets	17,266	17,296
Less accumulated amortization	(16,080)	(15,730)
Intangible assets, net	1,186	1,566
Client Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets	16,065	16,071
Less accumulated amortization	(7,409)	(5,829)
Intangible assets, net	$ 8,656	$ 10,242

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

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