STOCKHOLDERS' DEFICIT - Dividends (Narrative) (Details) - USD ($) $ in Millions						3 Months Ended
	Jan. 24, 2018	Oct. 31, 2017	Oct. 05, 2017	Feb. 23, 2017	Feb. 09, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Percentage of dividend received	89.50%	89.50%	89.50%
Proceeds received through subsidiaries	$ 26.8	$ 22.4	$ 22.4
Parent Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Percentage of dividend received				89.90%
Proceeds received through subsidiaries				$ 254.0
CCOH
Accumulated Other Comprehensive Income (Loss) [Line Items]
Payment of dividend	30.0	25.0	25.0		$ 282.5
Australia Outdoor | CCOH
Accumulated Other Comprehensive Income (Loss) [Line Items]
Aggregate purchase price in cash and certain advertising assets						$ 195.7
Public Stockholders | CCOH
Accumulated Other Comprehensive Income (Loss) [Line Items]
Payment of dividend	$ 3.2	$ 2.6	$ 2.6	$ 28.5
Payment of dividend, percentage paid	10.50%	10.50%	10.50%	10.10%
Majority Shareholder
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amount of demand for repayment			$ 25.0
Majority Shareholder | CCOH
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amount of demand for repayment	$ 30.0	$ 25.0