Other Receivables, Other Assets, Accounts Payable And Other Liabilities (Schedule Of Other Receivables) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Other Receivables, Other Assets, Accounts Payable And Other Liabilities [Abstract]
Cash collateral due from counterparties	$ 4,141	$ 6,216
Asset management fees receivable	966	947
New issue and advisory fees receivable		2,100
Accrued interest and dividend receivable	1,714	2,359
Revenue share receivable	96	140
Other receivables	354	310
Other receivables	$ 7,271	$ 12,072