Goodwill and Other Intangible Assets (Schedule of Finite and Indefinite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross	$ 790,445	$ 787,507
Accumulated Amortization	(418,567)	(396,735)
Net	371,878	390,772
Trademarks	19,900	19,900
Total intangible assets, gross	810,345	807,407
Total intangible assets, net	391,778	410,672
Affiliate and customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross	640,319	624,699
Accumulated Amortization	(348,061)	(330,350)
Net	292,258	294,349
Advertiser relationships
Finite-Lived Intangible Assets [Line Items]
Gross	46,282	46,282
Accumulated Amortization	(29,183)	(26,028)
Net	$ 17,099	20,254
Estimated useful lives (in years)	11 years
Trade names and other amortizable intangible assets
Finite-Lived Intangible Assets [Line Items]
Gross	$ 103,844	116,526
Accumulated Amortization	(41,323)	(40,357)
Net	$ 62,521	$ 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