Goodwill and Other Intangible Assets (Intangibles, Net) (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 105,775	$ 105,835
Less accumulated amortization	36,774	34,662
Intangible assets subject to amortization, net	69,001us-gaap_FiniteLivedIntangibleAssetsNet	71,173us-gaap_FiniteLivedIntangibleAssetsNet
Customer relationships
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	88,576	88,576
Non-compete agreements
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	13,163	13,223
Trade names
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	1,939	1,939
Other intangible assets
Goodwill and Other Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 2,097	$ 2,097

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

+ References

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.

+ 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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