GOODWILL AND RADIO BROADCASTING LICENSES - Goodwill Valuation Results (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
GOODWILL AND RADIO BROADCASTING LICENSES
Gross goodwill	$ 378,079
Additions	0
Impairments	0
Accumulated impairment losses	(154,207)
Entercom asset exchange	(470)
Net goodwill	223,402	$ 223,402
Radio Broadcasting Segment [Member]
GOODWILL AND RADIO BROADCASTING LICENSES
Gross goodwill	155,000
Additions	0
Impairments	0
Accumulated impairment losses	(117,748)
Entercom asset exchange	(470)
Net goodwill	36,782
Reach Media Segment [Member]
GOODWILL AND RADIO BROADCASTING LICENSES
Gross goodwill	30,468
Additions	0
Impairments	0
Accumulated impairment losses	(16,114)
Net goodwill	14,354
Digital Segment [Member]
GOODWILL AND RADIO BROADCASTING LICENSES
Gross goodwill	27,567
Additions	0
Impairments	0
Accumulated impairment losses	(20,345)
Net goodwill	7,222
Cable Television Segment [Member]
GOODWILL AND RADIO BROADCASTING LICENSES
Gross goodwill	165,044
Additions	0
Impairments	0
Accumulated impairment losses	0
Net goodwill	$ 165,044

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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