REVENUE - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	4 Months Ended	5 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	May 01, 2019	Sep. 30, 2019	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 743,829	$ 947,920	$ 1,072,775	$ 1,583,287	$ 2,011,248
Revenue from leases	577	418	696	697	1,440
Revenue, total	744,406	948,338	1,073,471	1,583,984	2,012,688
Eliminations
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	(1,930)	(1,899)	(2,568)	(3,020)	(5,855)
Revenue from leases	0	0	0	0	0
Revenue, total	(1,930)	(1,899)	(2,568)	(3,020)	(5,855)
Audio \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	670,720	889,946	1,005,981	1,485,897	1,842,586
Revenue from leases	577	418	696	697	1,440
Revenue, total	671,297	890,364	1,006,677	1,486,594	1,844,026
Audio and Media Services \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	75,039	59,873	69,362	100,410	174,517
Revenue from leases	0	0	0	0	0
Revenue, total	75,039	59,873	69,362	100,410	174,517
Broadcast Radio
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	404,460	573,048	657,864	963,588	1,110,155
Broadcast Radio \| Eliminations
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Broadcast Radio \| Audio \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	404,460	573,048	657,864	963,588	1,110,155
Broadcast Radio \| Audio and Media Services \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Digital
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	112,589	96,656	102,789	160,894	298,592
Digital \| Eliminations
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Digital \| Audio \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	112,589	96,656	102,789	160,894	298,592
Digital \| Audio and Media Services \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Networks
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	118,982	160,133	189,088	265,559	349,889
Networks \| Eliminations
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Networks \| Audio \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	118,982	160,133	189,088	265,559	349,889
Networks \| Audio and Media Services \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Sponsorship and Events
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	28,898	55,541	50,330	87,331	73,055
Sponsorship and Events \| Eliminations
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Sponsorship and Events \| Audio \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	28,898	55,541	50,330	87,331	73,055
Sponsorship and Events \| Audio and Media Services \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Audio and Media Services
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	73,277	58,142	67,037	97,670	169,165
Audio and Media Services \| Eliminations
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	(1,762)	(1,731)	(2,325)	(2,740)	(5,352)
Audio and Media Services \| Audio \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	0	0	0	0	0
Audio and Media Services \| Audio and Media Services \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	75,039	59,873	69,362	100,410	174,517
Other
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	5,623	4,400	5,667	8,245	10,392
Other \| Eliminations
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	(168)	(168)	(243)	(280)	(503)
Other \| Audio \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	5,791	4,568	5,910	8,525	10,895
Other \| Audio and Media Services \| Operating segments
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 0	$ 0	$ 0	$ 0	$ 0