Goodwill and Other Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Intangible Assets [Line Items]
Intangible amortization expense	$ 1,159	$ 1,164	$ 3,487	$ 3,492
Intangible assets subject to amortization, Cost	66,376		66,376		$ 66,376
Intangible assets subject to amortization, Accumulated Amortization	(34,425)		(34,425)		(30,939)
Intangible assets subject to amortization, Net Book Value	31,951		31,951		35,437
Customer relationships
Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost	55,454		55,454		55,454
Intangible assets subject to amortization, Accumulated Amortization	(28,045)		(28,045)		(25,587)
Intangible assets subject to amortization, Net Book Value	27,409		$ 27,409		$ 29,867
Customer relationships | Minimum
Intangible Assets [Line Items]
Average Life (Years)			12 years		12 years
Customer relationships | Maximum
Intangible Assets [Line Items]
Average Life (Years)			20 years		20 years
Technology and software
Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost	7,101		$ 7,101		$ 7,101
Intangible assets subject to amortization, Accumulated Amortization	(4,720)		(4,720)		(4,024)
Intangible assets subject to amortization, Net Book Value	2,381		$ 2,381		$ 3,077
Technology and software | Minimum
Intangible Assets [Line Items]
Average Life (Years)			7 years		7 years
Technology and software | Maximum
Intangible Assets [Line Items]
Average Life (Years)			10 years		10 years
Trademarks
Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost	3,330		$ 3,330		$ 3,330
Intangible assets subject to amortization, Accumulated Amortization	(1,169)		(1,169)		(877)
Intangible assets subject to amortization, Net Book Value	2,161		$ 2,161		$ 2,453
Trademarks | Minimum
Intangible Assets [Line Items]
Average Life (Years)			7 years 6 months		7 years 6 months
Trademarks | Maximum
Intangible Assets [Line Items]
Average Life (Years)			10 years		10 years
Non-compete agreements
Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost	491		$ 491		$ 491
Intangible assets subject to amortization, Accumulated Amortization	$ (491)		$ (491)		(451)
Intangible assets subject to amortization, Net Book Value					$ 40
Non-compete agreements | Minimum
Intangible Assets [Line Items]
Average Life (Years)			5 years		5 years
Non-compete agreements | Maximum
Intangible Assets [Line Items]
Average Life (Years)			8 years		8 years