Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 02, 2019
Cash segregated in special reserve bank account	$ 110,000
FDIC insured amount	250,000
Advertising costs	2,000	45,000
Income taxes receivable	141,000	79,000
Right-of-use assets	2,810,000
Lease liabilities	3,114,000
Note payable	$ 3,000,000
Promissory Note [Member] \| Weeden Prime Services LLC [Member]
Note payable			$ 3,000,000
Robo-Advisor [Member]
Estimated useful life of software	3 years
StockCross [Member]
Cash clearing deposits	$ 75,000	75,000
NFS [Member]
Cash clearing deposits	50,000	50,000
Goldman Sachs [Member]
Cash clearing deposits	2,000,000	2,000,000
Pershing [Member]
Cash clearing deposits	$ 1,100,000	$ 1,100,000

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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