Goodwill and Other Intangible Assets (Schedule of Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets
Gross Carrying Value	$ 88,181	$ 87,003
Accumulated Amortization	(30,741)	(23,484)
Net Carrying Amount	57,440	63,519
Non-competition agreements
Finite-Lived Intangible Assets
Gross Carrying Value	4,238	4,219
Accumulated Amortization	(3,100)	(2,217)
Net Carrying Amount	1,138	2,002
Patents
Finite-Lived Intangible Assets
Gross Carrying Value	389	373
Accumulated Amortization	(164)	(143)
Net Carrying Amount	225	230
Customer relationships
Finite-Lived Intangible Assets
Gross Carrying Value	37,679	36,843
Accumulated Amortization	(9,171)	(6,582)
Net Carrying Amount	28,508	30,261
Trademarks and trade names
Finite-Lived Intangible Assets
Gross Carrying Value	10,085	10,018
Accumulated Amortization	(4,091)	(3,238)
Net Carrying Amount	5,994	6,780
Technology
Finite-Lived Intangible Assets
Gross Carrying Value	35,790	35,550
Accumulated Amortization	(14,215)	(11,304)
Net Carrying Amount	$ 21,575	$ 24,246
Weighted Average
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	15 years
Weighted Average | Non-competition agreements
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	5 years	5 years
Weighted Average | Patents
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	10 years	10 years
Weighted Average | Customer relationships
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	17 years	18 years
Weighted Average | Trademarks and trade names
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	14 years	14 years
Weighted Average | Technology
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	14 years	14 years