ACQUISITIONS AND DISPOSITIONS (Details Textual) - USD ($)			1 Months Ended				6 Months Ended	12 Months Ended
	Aug. 08, 2018	Aug. 03, 2017	May 02, 2017	Apr. 28, 2017	Apr. 20, 2017	Jan. 30, 2017	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Aug. 09, 2018
Business Acquisition [Line Items]
Proceeds from Divestiture of Businesses		$ 2,000,000				$ 25,000,000
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Customer Relationship				$ 1,400,000
Sale Leaseback Transaction, Net Proceeds, Investing Activities			$ 25,000,000					$ 0	$ 25,000,000
Sale And Leaseback Transaction Gain			$ 22,500,000
Sale and Leaseback Transaction, Gain (Loss), Net							$ 14,400,000	0	14,411,000
Goodwill				4,600,000				245,572,000	262,894,000
Sale Leaseback Transaction, Deferred Gain, Net							$ 8,100,000	809,000	809,000
Business Acquisition Purchase Price Allocation Indefinite Live Intangible Assets Land And Land Improvements										$ 1,100,000
Business Acquisition Purchase Price Allocation Indefinite Live Intangible Assets Towers										512,000
Proceeds from Sale of Property Held-for-sale								$ 12,791,000	$ 2,000,000
Proceeds from Property Plant and Equipment Received in Cash	$ 12,200,000
Red Zebra Broadcasting [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total					$ 206,000
Business Acquisition Purchase Price Allocation Indefinite Lived Intangible Assets, Radio Broadcasting Licenses					1,600,000					2,000,000
Business Acquisition Purchase Price Allocation Indefinite Lived Intangible Assets Including Goodwill					47,000					91,000
Business Combination, Consideration Transferred					2,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Intangible Assets					$ 114,000
Business Acquisition Purchase Price Allocation Indefinite Live Intangible Assets Advertiser Agreements										206,000
Business Acquisition Purchase Price Allocation Indefinite Live Intangible Assets Other Property And Equipment										$ 254,000
Moguldom Media Group, LLC. [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total				22,000
Business Combination, Consideration Transferred				5,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Intangible Assets				322,000
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Brand and Trade Names				1,200,000
Business Combination, Contingent Consideration, Liability				2,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other				263,000
Goodwill				$ 5,000,000
Detroit radio station [Member]
Business Acquisition [Line Items]
Proceeds from Sale of Property Held-for-sale	$ 12,700,000