Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Intangible Assets, Net [Abstract]
Gross Carrying Amount	$ 96,618	$ 90,038
Accumulated Amortization	(48,526)	(38,972)
Net Carrying Amount	48,092	51,066
Customer relationships
Intangible Assets, Net [Abstract]
Gross Carrying Amount	82,478	75,407
Accumulated Amortization	(40,946)	(32,307)
Net Carrying Amount	41,532	43,100
Non-compete agreements
Intangible Assets, Net [Abstract]
Gross Carrying Amount	1,536	1,556
Accumulated Amortization	(735)	(707)
Net Carrying Amount	801	849
Customer Backlog
Intangible Assets, Net [Abstract]
Gross Carrying Amount	1,535	1,650
Accumulated Amortization	(736)	(866)
Net Carrying Amount	799	784
Trade name
Intangible Assets, Net [Abstract]
Gross Carrying Amount	140	100
Accumulated Amortization	(76)	(53)
Net Carrying Amount	64	47
Developed software
Intangible Assets, Net [Abstract]
Gross Carrying Amount	10,929	11,325
Accumulated Amortization	(6,033)	(5,039)
Net Carrying Amount	$ 4,896	$ 6,286

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- References

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph ((a)(1),(b))
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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