Income Taxes - Schedule of Components of Net Deferred Tax Asset Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Net operating loss carryforwards	$ 51,802	$ 26,657
Compensation	15,574	14,308
Rent	2,173	3,197
Transaction costs		8,238
Pension	28,033
Other	12,732	7,348
Total deferred tax assets	110,314	59,748
Valuation allowance for deferred tax assets	(2,155)
Total deferred tax assets	108,159	59,748
Deferred tax liabilities:
Property and equipment	(72,423)	(15,882)
Other intangible assets	(312,460)	(35,628)
Goodwill	(31,062)	(35,780)
FCC licenses	(305,293)	(98,494)
Other	(4,854)	(13)
Total deferred tax liabilities	(726,092)	(185,797)
Net deferred tax liabilities	$ (617,933)	$ (126,049)