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COMMITMENTS AND CONTINGENCIES - Narrative (Details) $ in Thousands								1 Months Ended	3 Months Ended		9 Months Ended
	Nov. 08, 2021 lawsuit	Jul. 28, 2021 USD ($)	Oct. 15, 2020 USD ($)	Sep. 02, 2020 USD ($)	Aug. 19, 2020 USD ($)	Jun. 08, 2020 petition	May 22, 2020 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Oct. 03, 2018 broadcaster
COMMITMENTS AND CONTINGENCIES
Interest expense including amortization of debt discount and deferred financing costs									$ (155,000)	$ (157,000)	$ (466,000)	$ (502,000)
Unfavorable Regulatory Action
COMMITMENTS AND CONTINGENCIES
Proposed fine				$ 9,000				$ 13,000
Proposed fine per station			$ 25	$ 500
Issuance of forfeiture penalty upheld		$ 500
Additional legal expenses accrued											8,000
Breach of Merger Agreement
COMMITMENTS AND CONTINGENCIES
Agreement to pay to resolve FCC investigation							$ 48,000
Payments for resolve FCC investigation					$ 48,000
Compliance plan term							4 years
Number of petitions filed \| petition						2
Various Cases Alleging Violation of Sherman Antitrust Act
COMMITMENTS AND CONTINGENCIES
Loss contingency, number of other broadcasters \| broadcaster														13
Various Cases Alleging Violation of Sherman Antitrust Act \| Subsequent Event
COMMITMENTS AND CONTINGENCIES
Loss contingency, new claims filed, number (lawsuit) \| lawsuit	22
Fixed Payment Obligations \| RSNs
COMMITMENTS AND CONTINGENCIES
Other current liabilities									32,000		32,000		$ 31,000
Other long-term liabilities									76,000		76,000		97,000
Interest expense including amortization of debt discount and deferred financing costs									(2,000)	(2,000)	(5,000)	(6,000)
Variable Payment Obligations \| RSNs
COMMITMENTS AND CONTINGENCIES
Other current liabilities									8,000		8,000		12,000
Other long-term liabilities									42,000		42,000		$ 41,000
Variable Payment Obligations \| RSNs \| Other Income, Net
COMMITMENTS AND CONTINGENCIES
Contingent consideration measurement adjustment (gain) loss									$ 1,000	$ (168,000)	$ 4,000	$ (168,000)