SUPPLEMENTAL CASH FLOW DISCLOSURES ON NON-CASH INVESTING AND FINANCING ACTIVITIES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash Flow Noncash [Line Items]
Net Paid In Captital Of Rsus	$ 34,511	$ 10,101	$ 8,336
Transition Services Costs incurred in Merger	1,917	0	0
Reduction in Transition Services Costs	(1,917)	0	0
Perpetual Cumulative Convertible Preferred Stock Issued For Acquisition	0	0	27,500
Dividend Accrued On Perpetual Cumulative Convertible Preferred Stock	0	452	339
Finance Method Lease Obligations Retirement	0	0	0
Net Radio Station Assets Given Up	124,500	0	59,000
Net Radio Station Assets Acquired	124,500	0	59,000
Radio Station Assets Acquired Using Preferred Stock	0	0	27,500
Cash acquired through consolidation of a VIE	(302)	302	0
Radio station assets acquired through the issuance of common stock	1,168,848	0	0
Barter And Other Transactions [Abstract]
Barter Revenues	10,898	4,700	4,002
Barter expenses	9,440	4,789	4,258
Issuance [Member]
Cash Flow Noncash [Line Items]
Net Paid In Captital Of Rsus	35,628	10,381	9,045
Forfeited [Member]
Cash Flow Noncash [Line Items]
Net Paid In Captital Of Rsus	$ 1,117	$ 280	$ 709