BUSINESS COMBINATIONS - Preliminary purchase price allocations (Details) - USD ($) $ in Thousands			6 Months Ended	12 Months Ended
	Apr. 20, 2021	Mar. 09, 2021	Jun. 30, 2021	Dec. 31, 2020	Nov. 09, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Goodwill			$ 81,826	$ 62,215		$ 43,920
Goodwill			32	$ (28)
Podcorn
Business Acquisition [Line Items]
Cash		$ 702	702
Cash		0
Prepaid expenses, deposits and other		18	18
Prepaid expenses, deposits and other		0
Other assets, net of accumulated amortization		2,545	2,545
Other assets, net of accumulated amortization		0
Goodwill		19,579	19,611
Goodwill		32
Deferred tax asset		72	72
Deferred tax asset		0
Net working capital		95	63
Net working capital		(32)
Preliminary fair value of net assets acquired		23,011	$ 23,011
Preliminary fair value of net assets acquired		$ 0
QL Gaming Group
Business Acquisition [Line Items]
Net property and equipment					$ 8
Other assets, net of accumulated amortization					14,608
Goodwill					18,323
Net working capital					12
Preliminary fair value of net assets acquired					31,603
Total intangible and other assets					32,931
Deferred tax liabilities					$ (1,348)
2021 Urban One Exchange
Business Acquisition [Line Items]
Net property and equipment	$ 2,254
Radio broadcasting licenses	23,233
Total intangible assets	23,233
Total assets	$ 25,487
2021 Urban One Exchange | Minimum
Business Acquisition [Line Items]
Useful Lives in Years	0 years
2021 Urban One Exchange | Maximum
Business Acquisition [Line Items]
Useful Lives in Years	40 years