Other Intangible Assets - Schedule of Other Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 77,586	$ 78,146
Less accumulated amortization	(67,181)	(50,583)
Intangible assets, net	10,405	27,563
Trade names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 2,510	2,510
Acquired finite-lived intangible assets, weighted average useful life	13 years 3 months 18 days
Customer lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 74,063	74,615
Acquired finite-lived intangible assets, weighted average useful life	14 years 5 months
Noncompete agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 956	964
Acquired finite-lived intangible assets, weighted average useful life	4 years 1 month
Patents [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 57	$ 57
Acquired finite-lived intangible assets, weighted average useful life	9 years