Goodwill and Other Intangible Assets (Schedule of Finite and Indefinite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross	$ 772,320	$ 787,507
Accumulated Amortization	(402,301)	(396,735)
Net	370,019	390,772
Trademarks	19,900	19,900
Total intangible assets, gross	792,220	807,407
Total intangible assets, net	389,919	410,672
Affiliate and customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross	621,136	624,699
Accumulated Amortization	(335,631)	(330,350)
Net	285,505	294,349
Advertiser relationships
Finite-Lived Intangible Assets [Line Items]
Gross	46,282	46,282
Accumulated Amortization	(27,080)	(26,028)
Net	$ 19,202	20,254
Estimated useful lives (in years)	11 years
Trade names and other amortizable intangible assets
Finite-Lived Intangible Assets [Line Items]
Gross	$ 104,902	116,526
Accumulated Amortization	(39,590)	(40,357)
Net	$ 65,312	$ 76,169
Minimum | Affiliate and customer relationships
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives (in years)	6 years
Minimum | Trade names and other amortizable intangible assets
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives (in years)	3 years
Maximum | Affiliate and customer relationships
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives (in years)	25 years
Maximum | Trade names and other amortizable intangible assets
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives (in years)	20 years