CONSOLIDATED STATEMENTS OF COMPHREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (5,795)us-gaap_ProfitLoss	$ 576us-gaap_ProfitLoss	$ 4,340us-gaap_ProfitLoss
Other comprehensive loss:
Change in cumulative translation adjustment	(10)	(118)	(273)
Other comprehensive loss, net of tax	(10)	(118)	(273)
Total comprehensive (loss) income	(5,805)	458	4,067
Comprehensive income (loss) attributable to noncontrolling interests	6	(482)	819
Comprehensive (loss) income attributable to B. Riley Financial, Inc.	$ (5,811)us-gaap_ComprehensiveIncomeNetOfTax	$ 940us-gaap_ComprehensiveIncomeNetOfTax	$ 3,248us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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