Revenue Recognition (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Stock borrow / stock loan	$ 771,000	$ 423,000	$ 1,215,000	$ 1,004,000
Gross revenue from stock borrow/ Stock loan	2,008,000	2,831,000	3,671,000	6,270,000
Expenses from stock borrow/stock loan	1,237,000	$ 2,408,000	2,456,000	$ 5,266,000
Client expenses	134,000		352,000
Other receivables	7,000		7,000
Accounts payable and accrued liabilities	$ 207,000		$ 207,000