Goodwill and Intangible Assets, Net Goodwill and Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 15,015	$ 16,003	$ 20,721
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	83	2,010	2,140
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	14,743	13,785	12,845
Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 189	$ 208	$ 5,736