ACQUISITIONS - Pro forma (Details) - Targus - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Business Acquisition [Line Items]
Revenues	$ 233,834	$ 575,121
Net loss	(135,394)	(142,707)
Net loss attributable to B. Riley Financial, Inc.	(138,965)	(147,144)
Net loss attributable to common shareholders	$ (140,967)	$ (151,148)

Business Acquisition, Pro Forma Net Income (Loss), Attributable To Parent

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- Definition

Business Acquisition, Pro Forma, Net Income (Loss) Available To Common Stockholders

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479907/805-20-50-5

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479328/805-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479328/805-10-50-2

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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