Goodwill And Other Intangible Assets - (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets not subject to amortization	$ 755,100	$ 755,100
Total other intangible assets, net (excluding goodwill)	1,529,698	1,613,665
Goodwill	3,228,774	3,228,988
Total goodwill and other intangible assets	4,758,472	4,842,653
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	1,588,523	1,588,750
Intangible assets, accumulated amortization	(813,925)	(730,185)
Intangible assets subject to amortization, net	774,598	858,565
FCC Licenses
Indefinite-lived Intangible Assets [Line Items]
Other intangible assets not subject to amortization	740,300	740,300
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	(72,875)	(66,250)
Intangible assets subject to amortization, net	$ 139,125	145,750
Affiliate Relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	16 years
Affiliate Relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
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	(115,500)	(105,000)
Intangible assets subject to amortization, net	$ 52,500	63,000
Advertiser relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	8 years
Advertiser relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	8 years
Network Affiliation Agreements
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross	$ 362,000	362,000
Intangible assets, accumulated amortization	(196,143)	(175,337)
Intangible assets subject to amortization, net	$ 165,857	186,663
Network Affiliation Agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful life (years)	5 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	(422,053)	(377,033)
Intangible assets subject to amortization, net	$ 408,047	453,067
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	$ 16,423	16,650
Intangible assets, accumulated amortization	(7,354)	(6,565)
Intangible assets subject to amortization, net	$ 9,069	$ 10,085
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