Net Capital Requirements (Details) $ in Thousands	Dec. 31, 2019 USD ($)
FBR & Co. ("FBR") [Member]
Net Capital Requirements (Textual)
Net capital	$ 106,283
Excess capital	103,322
FBR & Co. ("FBR") [Member] | Maximum [Member]
Net Capital Requirements (Textual)
Excess capital	2,961
MLV & Co. [Member]
Net Capital Requirements (Textual)
Net capital	642
Excess capital	637
MLV & Co. [Member] | Maximum [Member]
Net Capital Requirements (Textual)
Excess capital	5
B. Riley Wealth Management [Member]
Net Capital Requirements (Textual)
Net capital	5,187
Excess capital	4,708
B. Riley Wealth Management [Member] | Maximum [Member]
Net Capital Requirements (Textual)
Excess capital	$ 479