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COMMITMENTS AND CONTINGENCIES (Narrative) (Details)								3 Months Ended		9 Months Ended
COMMITMENTS AND CONTINGENCIES (Narrative) (Details)	Nov. 09, 2020 lawsuit	Oct. 15, 2020 USD ($)	Sep. 02, 2020 USD ($)	Aug. 19, 2020 USD ($)	Jul. 20, 2020 USD ($) shares	May 22, 2020 USD ($) petition	Dec. 21, 2017 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Oct. 03, 2018 lawsuit
COMMITMENTS AND CONTINGENCIES
Interest expense including amortization of debt discount and deferred financing costs								$ (157,000,000)	$ (129,000,000)	$ (502,000,000)	$ (237,000,000)
Various Cases Alleging Violation of Sherman Antitrust Act
COMMITMENTS AND CONTINGENCIES
Loss contingency, number of other broadcasters \| lawsuit												13
Breach of Merger Agreement
COMMITMENTS AND CONTINGENCIES
Agreement to pay to resolve FCC investigation						$ 48,000,000
Payments for resolve FCC investigation				$ 48,000,000
Compliance plan term						4 years
Number of petitions filed \| petition						2
Legal expense										2,500,000
Settlement Stipulation
COMMITMENTS AND CONTINGENCIES
Agreement to pay to resolve FCC investigation					$ 20,500,000
Compliance plan term					5 years
Aggregate amount of settlement fund to be used					$ 5,000,000
Share based compensation to be forfeited, canceled, or returned (shares) \| shares					638,298
Unfavorable Regulatory Action
COMMITMENTS AND CONTINGENCIES
Proposed fine			$ 9,000,000				$ 13,000,000
Proposed fine per station			$ 500,000
Fixed Payment Obligations \| RSNs
COMMITMENTS AND CONTINGENCIES
Other current liabilities								57,000,000		57,000,000
Other long-term liabilities								100,000,000		100,000,000
Interest expense including amortization of debt discount and deferred financing costs								(2,000,000)	$ (500,000)	(6,000,000)	$ (500,000)
Variable Payment Obligations \| RSNs
COMMITMENTS AND CONTINGENCIES
Other current liabilities								20,000,000		20,000,000
Other long-term liabilities								44,000,000		44,000,000
Other income, net \| Variable Payment Obligations \| RSNs
COMMITMENTS AND CONTINGENCIES
Total measurement adjustment gains								$ 168,000,000		$ (168,000,000)
Subsequent Event \| Various Cases Alleging Violation of Sherman Antitrust Act
COMMITMENTS AND CONTINGENCIES
Loss contingency, new claims filed, number (lawsuit) \| lawsuit	22
Subsequent Event \| Unfavorable Regulatory Action
COMMITMENTS AND CONTINGENCIES
Proposed fine per station		$ 25,000