Income Taxes (Schedule of Income Tax Expense) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current
Federal	$ (176,000)	$ 288,000
State and local	(82,000)	270,000
Total Current	(258,000)	558,000
Deferred
Federal	161,000	229,000
State and local	318,000	261,000
Total Deferred	479,000	490,000
Total Provision for income taxes	$ 221,000	$ 1,048,000	[1]

[1] Statement of income for the year ended December 31, 2019 represents the pro forma combination of Siebert and StockCross balances. See "Note 3 - Acquisitions" for additional detail.