Organization and Business Description (Details)				12 Months Ended
	Aug. 05, 2020 shares	Jun. 10, 2020 $ / shares	Oct. 31, 2019 shares	Dec. 31, 2020 Firm $ / shares	Dec. 31, 2019 $ / shares	Nov. 01, 2019
Organization and Business Description [Abstract]
Number of NYSE member firms through which all securities transactions are cleared | Firm				3
Common stock, par value (in dollars per share) | $ / shares		$ 0.01		$ 0.01	$ 0.01
Reverse stock split ratio		0.01
Associated Capital Group [Member]
Organization and Business Description [Abstract]
Shares distributed to shareholders in spin-off (in shares)	500,000
Morgan Group, Inc. [Member]
Organization and Business Description [Abstract]
Stock acquired (in shares)			500,000
Morgan Group, Inc. [Member] | Associated Capital Group [Member]
Organization and Business Description [Abstract]
Ownership interest			100.00%			100.00%
G.research, LLC [Member] | Associated Capital Group [Member]
Organization and Business Description [Abstract]
Stock acquired (in shares)			500,000
G.research, LLC [Member] | Morgan Group, Inc. [Member] | Associated Capital Group [Member]
Organization and Business Description [Abstract]
Ownership interest			83.30%