Intangible Assets, Net Estimated Useful Lives of Intangible Assets (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value as of Acquisition Date	$ 169,913
Weighted Average Estimated Useful Life in Years	19 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value as of Acquisition Date	$ 144,900
Weighted Average Estimated Useful Life in Years	20 years
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value as of Acquisition Date	$ 15,400
Weighted Average Estimated Useful Life in Years	29 years
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value as of Acquisition Date	$ 9,613
Weighted Average Estimated Useful Life in Years	1 year