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COMMITMENTS AND CONTINGENCIES (Narrative) (Details) $ in Millions				3 Months Ended
	May 06, 2020 USD ($) lawsuit	Aug. 09, 2018 USD ($)	Dec. 21, 2017 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Oct. 03, 2018 lawsuit
COMMITMENTS AND CONTINGENCIES
Interest expense and amortization of debt discount and deferred financing costs				$ 180.0	$ 54.0
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
Proposed fine		$ 1,000.0
Agreement to pay to resolve FCC investigation	$ 48.0
Compliance plan term	4 years
Estimated liability recorded				2.5
Unfavorable Regulatory Action
COMMITMENTS AND CONTINGENCIES
Proposed fine			$ 13.0
Subsequent Event \| Various Cases Alleging Violation of Sherman Antitrust Act
COMMITMENTS AND CONTINGENCIES
Loss contingency, new claims filed, number (lawsuit) \| lawsuit	22
Fixed Payment Obligations \| RSNs
COMMITMENTS AND CONTINGENCIES
Other current liabilities				56.0
Other long-term liabilities				147.0
Interest expense and amortization of debt discount and deferred financing costs				2.0
Variable Payment Obligations \| RSNs
COMMITMENTS AND CONTINGENCIES
Other current liabilities				30.0
Other long-term liabilities				205.0
Interest expense and amortization of debt discount and deferred financing costs				$ 3.0