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Subsidiary, Ownership Percentage, Noncontrolling Owner, Remaining

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Face amount or stated value per share of common stock.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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NONCONTROLLING INTERESTS (Details) $ / shares in Units, $ in Thousands	Oct. 22, 2026 USD ($) $ / shares shares	Oct. 21, 2026 $ / shares	Sep. 30, 2026 $ / shares	Dec. 31, 2025 $ / shares	Mar. 10, 2025	Jan. 06, 2025
Noncontrolling Interest [Line Items]
Common stock, par value (in dollars per share)			$ 0.0001	$ 0.0001
BRC Partners Opportunity Fund, LP
Noncontrolling Interest [Line Items]
Rate of equity interests			22.60%			86.60%
Subsequent Event \| Substitute Restricted Stock Award
Noncontrolling Interest [Line Items]
Outstanding (in shares) \| shares	1,866,000
Exchange ratio	2
Subsequent Event \| Short-Form Merger
Noncontrolling Interest [Line Items]
Cash payments \| $	$ 2,422
Cash paid per acquiree share (in dollars per share)	$ 8.88
Subsequent Event \| Common Stock, par value $0.0001 per share
Noncontrolling Interest [Line Items]
Common stock, par value (in dollars per share)		$ 0.0001
B. Riley Securities Holdings, Inc.
Noncontrolling Interest [Line Items]
Ownership, percentage			93.30%	90.70%
Minority interest, remaining					89.40%
B. Riley Securities Holdings, Inc. \| Subsequent Event
Noncontrolling Interest [Line Items]
Subsidiary, ownership percentage, parent (in percentage)	100.00%
B. Riley Securities Holdings, Inc. \| Minimum \| Subsequent Event
Noncontrolling Interest [Line Items]
Subsidiary, ownership percentage, parent (in percentage)		90.00%
B. Riley Securities Holdings, Inc. \| Capital Markets segment
Noncontrolling Interest [Line Items]
Ownership, percentage					0.60%
BRC Partners Opportunity Fund, LP \| BRC Trust \| Related Party
Noncontrolling Interest [Line Items]
Ownership, percentage						58.20%