Goodwill and Other Intangible Assets (Schedule of Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets
Gross Carrying Value	$ 81,686	$ 82,980
Accumulated Amortization	(37,131)	(33,144)
Net Carrying Amount	44,555	49,836
Non-compete agreements
Finite-Lived Intangible Assets
Gross Carrying Value	1,227	1,372
Accumulated Amortization	(1,140)	(1,046)
Net Carrying Amount	87	326
Patents
Finite-Lived Intangible Assets
Gross Carrying Value	369	358
Accumulated Amortization	(181)	(165)
Net Carrying Amount	188	193
Customer relationships
Finite-Lived Intangible Assets
Gross Carrying Value	36,807	37,129
Accumulated Amortization	(13,021)	(11,388)
Net Carrying Amount	23,786	25,741
Trademarks and trade names
Finite-Lived Intangible Assets
Gross Carrying Value	7,732	8,481
Accumulated Amortization	(3,382)	(3,416)
Net Carrying Amount	4,350	5,065
Technology
Finite-Lived Intangible Assets
Gross Carrying Value	35,551	35,640
Accumulated Amortization	(19,407)	(17,129)
Net Carrying Amount	$ 16,144	$ 18,511
Weighted Average
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	15 years
Weighted Average | Non-compete agreements
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	4 years	4 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	18 years	18 years
Weighted Average | Trademarks and trade names
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	16 years	15 years
Weighted Average | Technology
Finite-Lived Intangible Assets
Weighted Average Amortization Period In Years	14 years	14 years