Intangibles and Other Assets, net (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Total intangibles, net	$ 83,941	$ 92,061
Deferred financing costs, net of accumulated amortization of $4,654 for 2019 and $4,331 for 2018 (see Note 11)	969	1,291
Accumulated amortization of debt issuance costs	4,654	4,331
Other assets	2,391	1,742
Total other assets, net	3,360	3,033
Intangibles and other assets, net	87,301	95,094
Developed technology and application patents
Finite-Lived Intangible Assets [Line Items]
Total intangibles, net	9,639	11,606
Accumulated amortization	$ 36,636	34,669
Developed technology and application patents | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	7 years
Developed technology and application patents | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	20 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Total intangibles, net	$ 63,247	67,479
Accumulated amortization	$ 32,265	28,032
Customer relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	5 years
Customer relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	20 years
Trade names and license agreements
Finite-Lived Intangible Assets [Line Items]
Total intangibles, net	$ 11,055	12,962
Accumulated amortization	$ 16,506	14,599
Trade names and license agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	5 years
Trade names and license agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	20 years
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Total intangibles, net	$ 0	14
Accumulated amortization	$ 1,333	$ 1,319
Non-compete agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	3 years
Non-compete agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (in years)	10 years