Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets, Gross [Abstract]
Finite-Lived Customer Lists, Gross	$ 74,574	$ 74,989
Trademarks, Formulations And Product Technology, Gross	33,128	33,275
Other Finite-Lived Intangible Assets, Gross	5,826	5,840
Total	113,528	114,104
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	53,207	51,622
Customer Lists [Member]
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	30,565	29,587
Trademarks, Formulations And Product Technology [Member]
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	17,011	16,469
Other Intangible Assets [Member]
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Accumulated Amortization	$ 5,631	$ 5,566