QUARTERLY FINANCIAL DATA (UNAUDITED AND RESTATED) - Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021
CURRENT ASSETS:
Trade accounts receivable, net of allowance for doubtful accounts of $8,811 and $8,743, respectively	$ 143,264	$ 127,666	$ 124,350	$ 114,112	$ 127,759	$ 114,356	$ 104,060	$ 94,914
Other current assets	8,372	7,676	6,774	7,134	3,497	3,160	2,997	3,376
Total current assets	289,747	286,190	310,150	325,305	312,324	270,642	278,630	202,911
RIGHT OF USE ASSETS	31,879	34,131	34,035	36,201	37,956	39,481	42,140	40,372
RADIO BROADCASTING LICENSES	488,419	495,832	487,640	501,420	501,420	503,524	503,524	482,442
OTHER INTANGIBLE ASSETS, net	55,193	57,367	59,422	61,564	47,921	49,508	50,744	51,988
DEBT SECURITIES - available-for-sale, at fair value; amortized cost of $40,000 at December 31, 2022 and 2021	136,826	115,600	123,100	123,000	112,600	110,800	106,400	101,900
OTHER ASSETS	5,688	6,434	6,658	6,285	6,956	25,341	5,583	5,523
Total assets	1,338,487	1,322,693	1,335,248	1,363,064	1,329,025	1,305,756	1,299,275	1,217,989
CURRENT LIABILITIES:
Accounts payable	18,003	16,276	16,934	14,306	16,892	16,656	14,590	11,165
Other current liabilities	36,320	38,624	29,582	33,776	24,430	27,612	22,228	23,175
Total current liabilities	130,263	112,999	109,997	100,162	106,784	88,296	99,315	78,254
DEFERRED TAX LIABILITIES, net	39,704	31,284	30,368	26,843	18,877	19,115	11,778	4,299
Total liabilities	979,417	982,345	996,163	1,015,525	1,006,690	989,468	999,823	961,765
REDEEMABLE NONCONTROLLING INTERESTS	25,298	22,327	20,434	20,227	18,655	19,328	17,649	14,524
STOCKHOLDERS' EQUITY:
Accumulated other comprehensive income	73,227	57,225	62,921	62,846	54,950	53,551	50,239	46,847
Additional paid-in capital	993,484	994,591	992,934	1,018,239	1,018,996	1,018,961	1,021,001	1,001,905
Accumulated deficit	(732,988)	(733,844)	(737,251)	(753,824)	(770,317)	(775,603)	(789,488)	(807,101)
Total stockholders' equity	333,772	318,021	318,651	327,312	303,680	296,960	281,803	241,700
Total liabilities, redeemable noncontrolling interests and stockholders' equity	$ 1,338,487	1,322,693	1,335,248	1,363,064	1,329,025	1,305,756	1,299,275	1,217,989
As Previously Reported
CURRENT ASSETS:
Trade accounts receivable, net of allowance for doubtful accounts of $8,811 and $8,743, respectively		127,301	123,998	113,687	127,446	114,045	103,902	94,633
Other current assets		8,939	8,037	8,397	4,760	4,423	4,260	4,639
Total current assets		287,088	311,061	326,143	313,274	271,594	279,735	203,893
RIGHT OF USE ASSETS		34,258	34,149	36,302	38,044	39,556	42,202	40,421
RADIO BROADCASTING LICENSES		498,532	489,340	505,148	505,148	505,148	505,148	484,066
OTHER INTANGIBLE ASSETS, net		59,376	61,508	63,727	50,159	51,821	53,059	54,375
DEFERRED TAX ASSETS, net							3,933	10,051
OTHER ASSETS		44,303	44,463	44,026	44,635	62,958	43,211	43,092
Total assets		1,250,696	1,254,764	1,284,635	1,261,108	1,237,537	1,239,542	1,168,751
CURRENT LIABILITIES:
Accounts payable		14,318	14,819	11,997	14,588	14,623	12,523	9,037
Other current liabilities		40,217	31,345	35,660	26,421	29,334	24,137	25,022
Total current liabilities		112,634	109,645	99,737	106,471	87,985	99,157	77,973
DEFERRED TAX LIABILITIES, net		13,984	11,070	8,059	2,473	2,325
Total liabilities		964,680	976,513	996,316	989,973	972,367	987,887	957,185
REDEEMABLE NONCONTROLLING INTERESTS		19,964	18,690	17,755	17,015	17,017	15,192	12,735
STOCKHOLDERS' EQUITY:
Additional paid-in capital		996,954	994,678	1,020,711	1,020,636	1,021,272	1,023,458	1,003,694
Accumulated deficit		(730,951)	(735,164)	(750,198)	(766,567)	(773,170)	(787,046)	(804,912)
Total stockholders' equity		266,052	259,561	270,564	254,120	248,153	236,463	198,831
Total liabilities, redeemable noncontrolling interests and stockholders' equity		1,250,696	1,254,764	1,284,635	1,261,108	1,237,537	1,239,542	1,168,751
Adjustments
CURRENT ASSETS:
DEFERRED TAX ASSETS, net							(3,933)	(10,051)
DEBT SECURITIES - available-for-sale, at fair value; amortized cost of $40,000 at December 31, 2022 and 2021		115,600	123,100	123,000	112,600	110,800	106,400	101,900
OTHER ASSETS		(40,000)	(40,000)	(40,000)	(40,000)	(40,000)	(40,000)	(40,000)
Total assets		75,600	83,100	83,000	72,600	70,800	62,467	51,849
CURRENT LIABILITIES:
DEFERRED TAX LIABILITIES, net		18,259	20,012	19,987	17,617	17,505	12,493	5,002
Total liabilities		18,259	20,012	19,987	17,617	17,505	12,493	5,002
STOCKHOLDERS' EQUITY:
Accumulated other comprehensive income		57,225	62,921	62,846	54,950	53,551	50,239	46,847
Accumulated deficit		116	167	167	33	(256)	(265)
Total stockholders' equity		57,341	63,088	63,013	54,983	53,295	49,974	46,847
Total liabilities, redeemable noncontrolling interests and stockholders' equity		75,600	83,100	83,000	72,600	70,800	62,467	51,849
Other Adjustments
CURRENT ASSETS:
Trade accounts receivable, net of allowance for doubtful accounts of $8,811 and $8,743, respectively		365	352	425	313	311	158	281
Other current assets		(1,263)	(1,263)	(1,263)	(1,263)	(1,263)	(1,263)	(1,263)
Total current assets		(898)	(911)	(838)	(950)	(952)	(1,105)	(982)
RIGHT OF USE ASSETS		(127)	(114)	(101)	(88)	(75)	(62)	(49)
RADIO BROADCASTING LICENSES		(2,700)	(1,700)	(3,728)	(3,728)	(1,624)	(1,624)	(1,624)
OTHER INTANGIBLE ASSETS, net		(2,009)	(2,086)	(2,163)	(2,238)	(2,313)	(2,315)	(2,387)
OTHER ASSETS		2,131	2,195	2,259	2,321	2,383	2,372	2,431
Total assets		(3,603)	(2,616)	(4,571)	(4,683)	(2,581)	(2,734)	(2,611)
CURRENT LIABILITIES:
Accounts payable		1,958	2,115	2,309	2,304	2,033	2,067	2,128
Other current liabilities		(1,593)	(1,763)	(1,884)	(1,991)	(1,722)	(1,909)	(1,847)
Total current liabilities		365	352	425	313	311	158	281
DEFERRED TAX LIABILITIES, net		(959)	(714)	(1,203)	(1,213)	(715)	(715)	(703)
Total liabilities		(594)	(362)	(778)	(900)	(404)	(557)	(422)
REDEEMABLE NONCONTROLLING INTERESTS		2,363	1,744	2,472	1,640	2,311	2,457	1,789
STOCKHOLDERS' EQUITY:
Additional paid-in capital		(2,363)	(1,744)	(2,472)	(1,640)	(2,311)	(2,457)	(1,789)
Accumulated deficit		(3,009)	(2,254)	(3,793)	(3,783)	(2,177)	(2,177)	(2,189)
Total stockholders' equity		(5,372)	(3,998)	(6,265)	(5,423)	(4,488)	(4,634)	(3,978)
Total liabilities, redeemable noncontrolling interests and stockholders' equity		$ (3,603)	$ (2,616)	$ (4,571)	$ (4,683)	$ (2,581)	$ (2,734)	$ (2,611)