Goodwill And Other Intangible Assets - (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets not subject to amortization	$ 752,000	$ 752,000
Total other intangible assets, net (excluding goodwill)	1,405,559	1,442,456
Goodwill	3,228,436	3,228,601
Total goodwill and other intangible assets	4,633,995	4,671,057
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	1,447,593	1,454,815
Intangible assets, accumulated amortization	(794,034)	(764,359)
Intangible assets subject to amortization, net	653,559	690,456
FCC Licenses
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets not subject to amortization	737,200	737,200
Trade Names
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets not subject to amortization	14,800	14,800
Affiliate Relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	212,000	212,000
Intangible assets, accumulated amortization	(82,813)	(79,500)
Intangible assets subject to amortization, net	$ 129,187	132,500
Useful life (years)	16 years
Advertiser relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 168,000	168,000
Intangible assets, accumulated amortization	(131,250)	(126,000)
Intangible assets subject to amortization, net	$ 36,750	42,000
Useful life (years)	8 years
Network Affiliation Agreements
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 228,700	228,700
Intangible assets, accumulated amortization	(87,401)	(83,649)
Intangible assets subject to amortization, net	$ 141,299	145,051
Network Affiliation Agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	11 years
Network Affiliation Agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	16 years
Retransmission Consent Agreements
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 830,100	830,100
Intangible assets, accumulated amortization	(489,582)	(467,073)
Intangible assets subject to amortization, net	$ 340,518	363,027
Retransmission Consent Agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	7 years
Retransmission Consent Agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	12 years
Other Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 8,793	16,015
Intangible assets, accumulated amortization	(2,988)	(8,137)
Intangible assets subject to amortization, net	$ 5,805	$ 7,878
Other Intangible Assets | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	5 years
Other Intangible Assets | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	15 years