Intangible Assets - Components of Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 33,331		$ 33,331
Less accumulated amortization	(24,603)		(24,079)
Intangible assets, net	8,728	$ 9,252	9,252
Covenants Not-to-Compete [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets	17,266		17,266
Less accumulated amortization	(16,301)		(16,198)
Intangible assets, net	965		1,068
Client Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets	16,065		16,065
Less accumulated amortization	(8,302)		(7,881)
Intangible assets, net	$ 7,763		$ 8,184

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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