Operating Expenses (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 29,112	$ 29,021	$ 28,337
Amortization expense	41,389	37,593	24,357
Software [Member]
Property, Plant and Equipment [Line Items]
Depreciation expense	410	494	1,207
Amortization expense	$ 27,944	$ 18,996	$ 11,662