Intangible Assets and Goodwill - Definite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount		$ 117,300
Accumulated amortization	$ (10,405)	(10,182)
Net intangible assets	$ 96,713	107,118
Weighted average remaining years of useful life	11 years
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount		82,300
Accumulated amortization	$ (6,539)	(6,398)
Net intangible assets	$ 69,363	75,902
Weighted average remaining years of useful life	11 years
Trademark
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount		10,900
Accumulated amortization	$ (850)	(832)
Net intangible assets	$ 9,218	10,068
Weighted average remaining years of useful life	13 years
Developed Technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount		24,100
Accumulated amortization	$ (3,016)	(2,952)
Net intangible assets	$ 18,132	$ 21,148
Weighted average remaining years of useful life	6 years