Intangible Assets - Components of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 33,378	$ 33,367
Less accumulated amortization	(22,308)	(21,559)
Intangible assets, net	11,070us-gaap_FiniteLivedIntangibleAssetsNet	11,808us-gaap_FiniteLivedIntangibleAssetsNet
Covenants Not-to-Compete [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets	17,313	17,296
Less accumulated amortization	(15,879)	(15,730)
Intangible assets, net	1,434	1,566
Client Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets	16,065	16,071
Less accumulated amortization	(6,429)	(5,829)
Intangible assets, net	$ 9,636	$ 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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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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