Goodwill and Intangible Assets, Summary of Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	$ 76,881	$ 67,395
Accumulated Amortization	(21,548)	(21,290)
Net Carrying Amounts	55,333	46,105
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	65,290	54,389
Accumulated Amortization	(18,770)	(16,595)
Net Carrying Amounts	46,520	37,794
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	1,573	1,601
Accumulated Amortization	(882)	(866)
Net Carrying Amounts	691	735
Customer Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	1,040	2,341
Accumulated Amortization	(391)	(2,265)
Net Carrying Amounts	649	76
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	88	167
Accumulated Amortization	(36)	(148)
Net Carrying Amounts	52	19
Internally Developed Software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	8,890	8,897
Accumulated Amortization	(1,469)	(1,416)
Net Carrying Amounts	$ 7,421	$ 7,481

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

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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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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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