Commitments and Contingencies (Details) $ in Thousands				1 Months Ended	3 Months Ended				6 Months Ended		12 Months Ended	49 Months Ended
	Mar. 23, 2018 USD ($)	Aug. 16, 2017	Dec. 08, 2008 subsidiary	Feb. 29, 2012 USD ($)	Jun. 30, 2018 USD ($) claim	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) claim	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) case	Dec. 31, 2012 claim	Aug. 09, 2018 television_station radio_station	Apr. 13, 2017 station	Dec. 31, 2016 USD ($)	Aug. 12, 2016 case
Loss Contingencies [Line Items]
Number of direct and indirect wholly-owned subsidiaries included in bankruptcy filing | subsidiary			110
Number of proofs of claim settled or satisfied pursuant to the terms of the plan | case																106
Number of complaints filed | claim												7,400
Restricted cash and cash equivalents					$ 16,607			$ 17,566	$ 16,607	$ 17,566	$ 17,566				$ 17,566
Number of proofs of claim subject to further evaluation and adjustments | claim					403				403
Reorganization Items					$ (685)			$ (449)	$ (1,578)	(699)
Federal Communications Commission Regulation, Television Station Ownership Cap, Percent					39.00%				39.00%
The UHF Discount, Percent					50.00%				50.00%
FCC regulation, maximum reimbursement amount for required product modifications				$ 1,750,000
FCC regulation, additional reimbursement amount for required product modifications	$ 1,000,000
Proceeds Received From FCC Spectrum Auction											191,000
Repayments of long-term debt									$ 0	$ 589,661
Proceeds from FCC spectrum auction											172,000
Proceeds from Spectrum, Sharing Arrangement, Pretax											84,000
Payments for Spectrum, Sharing Arrangements, Pretax											$ 66,000
Deferred Revenue and Other LT Liability, Useful Lives, Spectrum									30 years
Prepaid and Other LT Asset, Useful Lives, Spectrum									30 years
Number of Stations Subject to Spectrum Frequency Transition | station														22
Loss Contingency, Number of Filed Complaints | case											4
Third Party Involved in Claim, Participated in the Sale		4
Third Party Involved in Claim, Confidentiality Agreement		23
FCC Licenses
Loss Contingencies [Line Items]
(Gain) Loss on Disposition of Intangible Assets						$ (133,000)
Amended Secured Credit Facility | Term Loan Facility
Loss Contingencies [Line Items]
Repayments of long-term debt							$ 102,000				$ 102,000
Dreamcatcher Credit Facility Due 2018
Loss Contingencies [Line Items]
Repayments of long-term debt											12,600
Dreamcatcher Stations
Loss Contingencies [Line Items]
Proceeds Received From FCC Spectrum Auction											$ 26,000
Repayments of long-term debt							$ 12,600
Subsequent Event
Loss Contingencies [Line Items]
FCC regulation, number of television stations authorized | television_station													39
FCC regulation, number of radio stations authorized | radio_station													1