Receivables From, Payables To, and Deposits With Broker-Dealers and Clearing Organizations (Schedule of Receivable) (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Receivables from and deposits with broker-dealers and clearing organizations
DTCC / OCC / NSCC	$ 4,461,000	$ 3,059,000
Goldman Sachs	2,676,000	2,841,000
Pershing Capital	1,195,000	1,192,000
NFS	972,000	1,328,000
Securities fail-to-deliver	19,000	43,000
Globalshares	8,000	2,000
ICBC		10,000
Total Receivables from and deposits with broker-dealers and clearing organizations	9,331,000	8,475,000
Payables to broker-dealers and clearing organizations
Securities fail-to-receive	3,582,000	523,000
Total Payables to broker-dealers and clearing organizations	$ 3,582,000	$ 523,000