GOODWILL, RADIO BROADCASTING LICENSES AND OTHER INTANGIBLE ASSETS - Reach Media 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
Reach Media 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		10.50%		10.50%
Year 1 Revenue Growth Rate		(9.70%)		2.30%
Long-term Revenue Growth Rate (Year 5)		1.00%		1.00%
Minimum [Member] | Reach Media Segment Goodwill [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Operating Profit Margin Range		13.30%		14.60%
Maximum [Member] | Reach Media Segment Goodwill [Member]
Schedule of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Operating Profit Margin Range		14.30%		15.80%