GOODWILL, RADIO BROADCASTING LICENSES AND OTHER INTANGIBLE ASSETS - Digital Segment (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
Digital Segment [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Impairment charge (in millions)		$ 5.8
Discount Rate		12.00%		13.50%
Year 1 Revenue Growth Rate		12.20%		12.60%
Digital Segment [Member] | Maximum [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Long-term Revenue Growth Rate (Years 6 - 10)		7.70%		3.70%
Operating Profit Margin Range		11.70%		15.70%
Digital Segment [Member] | Minimum [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Long-term Revenue Growth Rate (Years 6 - 10)		2.80%		3.10%
Operating Profit Margin Range		(4.70%)		(1.10%)