Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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DEBT - Senior notes (Details) - USD ($)	3 Months Ended		12 Months Ended
DEBT - Senior notes (Details) - USD ($)	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2021	Dec. 30, 2021	Dec. 28, 2021	Mar. 31, 2021	Feb. 12, 2021
Debt Instrument [Line Items]
Issuance of senior notes	$ 8,000	$ 2,016,000
Senior notes \| B. Riley Financial, Inc.
Debt Instrument [Line Items]
Debt face amount							$ 35,000,000
8.125% Senior Notes due 2026 \| Senior notes
Debt Instrument [Line Items]
Debt interest rate per annum	8.125%		8.125%				8.125%
Issuance of senior notes			$ 151,200,000
Proceeds from issuance of debt, net			$ 146,600,000
8.125% Senior Notes due 2026 \| Senior notes \| B. Riley Financial, Inc.
Debt Instrument [Line Items]
Debt face amount							$ 35,000,000.0
8.125% Senior Notes due 2026 \| Senior notes \| B. Riley Securities, Inc.
Debt Instrument [Line Items]
Debt face amount						$ 150,000,000
6.50% Senior Notes \| Senior notes
Debt Instrument [Line Items]
Debt interest rate per annum	6.50%		6.50%	6.50%	6.50%
Issuance of senior notes			$ 151,400,000
Proceeds from issuance of debt, net			$ 145,800,000
Debt face amount					$ 11,400,000