Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Goodwill, Subsequent Recognition of Deferred Tax Asset	$ 332
Finite-Lived Intangible Assets, Amortization Expense	10,300	$ 9,300
National Networks
Finite-Lived Intangible Assets [Line Items]
Goodwill, Subsequent Recognition of Deferred Tax Asset	$ 332