GOODWILL, RADIO BROADCASTING LICENSES AND OTHER INTANGIBLE ASSETS - Cable Television Segment Goodwill (Details) - USD ($) $ in Millions	Dec. 31, 2019	Oct. 01, 2019	Dec. 31, 2018	Oct. 01, 2018
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Impairment charge (in millions)	$ 10.6		$ 21.3
Cable Television Segment Goodwill [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Impairment charge (in millions)		$ 0.0		$ 0.0
Discount Rate		10.00%		11.00%
Year 1 Revenue Growth Rate		1.00%		1.80%
Cable Television Segment Goodwill [Member] | Maximum [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Long-term Revenue Growth Rate Range (Years 6 - 10)		2.30%		3.00%
Operating Profit Margin Range		45.50%		42.50%
Cable Television Segment Goodwill [Member] | Minimum [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Long-term Revenue Growth Rate Range (Years 6 - 10)		1.90%		2.00%
Operating Profit Margin Range		33.00%		36.90%