Goodwill and Other Intangible Assets - Intangible Assets Subject to Amortization (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 97,642
Accumulated Amortization		(61,618)
Net Book Value		36,024
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		3,500
Accumulated Amortization		(1,140)
Net Book Value		2,360
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		94,142
Accumulated Amortization		(60,478)
Net Book Value		$ 33,664

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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