Goodwill, Other Intangible Assets and Intangible Liabilities - Goodwill, other Intangible Assets and Intangible Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 1,588,750	$ 1,587,548
Finite-Lived Intangible Assets, Accumulated Amortization	(730,185)	(562,414)
Finite-Lived Intangible Assets, Net	858,565	1,025,134	$ 1,192,602
Other intangible assets not subject to amortization	755,100	794,000	797,400
Total other intangible assets, net	1,613,665	1,819,134
Goodwill	3,228,988	3,227,930	$ 3,228,224
Total goodwill and other intangible assets	4,842,653	5,047,064
FCC licenses
Finite-Lived Intangible Assets [Line Items]
Other intangible assets not subject to amortization	740,300	779,200
Trade name
Finite-Lived Intangible Assets [Line Items]
Other intangible assets not subject to amortization	14,800	14,800
Affiliate relationships
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	212,000	212,000
Finite-Lived Intangible Assets, Accumulated Amortization	(66,250)	(53,000)
Finite-Lived Intangible Assets, Net	$ 145,750	159,000
Affiliate relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	16 years
Affiliate relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	16 years
Advertiser relationships
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 168,000	168,000
Finite-Lived Intangible Assets, Accumulated Amortization	(105,000)	(84,000)
Finite-Lived Intangible Assets, Net	$ 63,000	84,000
Advertiser relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	8 years
Advertiser relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	8 years
Network affiliation agreements
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 362,000	362,000
Finite-Lived Intangible Assets, Accumulated Amortization	(175,337)	(133,725)
Finite-Lived Intangible Assets, Net	$ 186,663	228,275
Network affiliation agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	5 years
Network affiliation agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	16 years
Retransmission consent agreements
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 830,100	830,100
Finite-Lived Intangible Assets, Accumulated Amortization	(377,033)	(286,994)
Finite-Lived Intangible Assets, Net	$ 453,067	543,106
Retransmission consent agreements | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	7 years
Retransmission consent agreements | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	12 years
Other
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 16,650	15,448
Finite-Lived Intangible Assets, Accumulated Amortization	(6,565)	(4,695)
Finite-Lived Intangible Assets, Net	$ 10,085	$ 10,753
Other | Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	5 years
Other | Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life (years)	15 years