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RELATED PARTY TRANSACTIONS (Details) - USD ($)		1 Months Ended	3 Months Ended
RELATED PARTY TRANSACTIONS (Details) - USD ($)	Mar. 10, 2021	Mar. 31, 2022	Mar. 31, 2022	Mar. 31, 2021	Mar. 09, 2022	Jan. 03, 2022	Dec. 31, 2021	Nov. 01, 2021
Related Party Transaction [Line Items]
Due from related party		$ 1,480,000	$ 1,480,000				$ 2,306,000
Interest expense			30,436,000	$ 19,786,000
Loans receivable, at fair value		$ 154,862,000	154,862,000				167,744,000
Underwriting and financial advisory and other fees			$ 1,880,000
Executive Officer's and Board of Directors
Related Party Transaction [Line Items]
Financial interest		49.10%	49.10%
Funds from Mananagement Fees
Related Party Transaction [Line Items]
Due from related party		$ 1,088,000	$ 1,088,000				621,000
CA Global Partners, LLC
Related Party Transaction [Line Items]
Due from related party							1,635,000
Other operating expenses			442,000
B. Riley Partners Opportunity Fund
Related Party Transaction [Line Items]
Interest expense			0	346,000
Commissions trade Income			$ 0	330,000
B. Riley Partners Opportunity Fund \| Co-Chief Executive Officer
Related Party Transaction [Line Items]
Financial interest		29.10%	29.10%
Whitehawk Capital Partners, L.P.
Related Party Transaction [Line Items]
Management fees			$ 1,079,000	1,210,000
Babcock and Wilcox
Related Party Transaction [Line Items]
Underwriting and financial advisory fees			53,000	$ 10,638,000
Services fees			750,000
Performance fee		$ 1,000,000
The Arena Group Holdings, Inc.
Related Party Transaction [Line Items]
Loans receivable, at fair value		$ 67,988,000	$ 67,988,000				69,835,000
Interest on loan payable percentage			10.00%
Revenue from related parties			$ 2,021,000
Lingo
Related Party Transaction [Line Items]
Financial interest		16.00%	16.00%
Loans receivable, at fair value		$ 71,842,000	$ 71,842,000				58,565,000
Conversion feature, principal amount		$ 17,500,000	$ 17,500,000
Extended promissory note	$ 1,100,000
Interest bears		6.00%	6.00%
California Natural Resources Group, LLC
Related Party Transaction [Line Items]
Loans receivable, at fair value		$ 9,540,000	$ 9,540,000		$ 10,000,000			$ 34,393,000
Interest bears		7.00%	7.00%					10.00%
Loans receivable, accordion feature amount					$ 10,000,000
California Natural Resources Group, LLC \| Indirect Guarantee of Indebtedness
Related Party Transaction [Line Items]
Debt and lease obligation						$ 10,375,000
Other Related Party
Related Party Transaction [Line Items]
Loans receivable, at fair value		$ 4,417,000	$ 4,417,000				$ 4,201,000
Minimum \| Lingo
Related Party Transaction [Line Items]
Financial interest		40.00%	40.00%
Maximum \| Lingo
Related Party Transaction [Line Items]
Financial interest		80.00%	80.00%