NET CAPITAL REQUIREMENTS (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
B. Riley Securities (“BRS”)
Broker-Dealer, Net Capital Requirement [Line Items]
Net capital	$ 146,622	$ 175,503
Excess capital	142,616	169,458
Required minimum net capital		6,045
B. Riley Wealth Management (“BRWM”)
Broker-Dealer, Net Capital Requirement [Line Items]
Net capital	4,006	11,144
Excess capital	17,254	8,615
Required minimum net capital		$ 2,529
National Securities Corporation (“NSC”)
Broker-Dealer, Net Capital Requirement [Line Items]
Net capital	15,469
Excess capital	$ 1,785

Broker Dealer, Net Capital Requirement [Line Items]

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Amount of net capital in excess of minimum required net capital, calculated under Alternative Standard.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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Minimum amount of net capital of broker-dealer and its subsidiary, calculated under Alternative Standard.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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Amount of net capital of broker-dealer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Rule 15c3-1
-Number 240
-Section 15c3-1
-Publisher SEC

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