NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Nature of Operations (Details)	3 Months Ended
Mar. 31, 2020 channel segment station regional_sport_network professional_team market	Aug. 29, 2019
Schedule of Equity Method Investments [Line Items]
Number of reportable segments \| segment	2
Number of television stations owned \| station	191
Number of markets \| market	89
Number of channels \| channel	631
Number of professional sports team with exclusive regional distribution rights \| professional_team	44
YES Network
Schedule of Equity Method Investments [Line Items]
Equity interest percentage	20.00%	20.00%
Sports \| Operating segments
Schedule of Equity Method Investments [Line Items]
Number of regional sports networks acquired \| regional_sport_network	21

Business Acquisition, Number Of Regional Sports Network Brands Acquired

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Number Of Professional Sports Teams With Exclusive Regional Distribution Rights

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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