Receivables From, Payables To, and Deposits With Broker-Dealers and Clearing Organizations (Schedule of Receivable) (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Receivables from and deposits with broker-dealers and clearing organizations
DTCC / OCC / NSCC	$ 2,956,000	$ 3,059,000
Goldman Sachs	2,763,000	2,841,000
Pershing Capital	1,467,000	1,192,000
NFS	1,348,000	1,328,000
Securities fail-to-deliver	24,000	43,000
Globalshares	16,000	2,000
ICBC	10,000	10,000
Total Receivables from and deposits with broker-dealers and clearing organizations	8,584,000	8,475,000
Payables to broker-dealers and clearing organizations
NFS	727,000
Securities fail-to-receive	306,000	523,000
Total Payables to broker-dealers and clearing organizations	$ 1,033,000	$ 523,000