Investment Securities (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($) security shares	Mar. 31, 2019 USD ($) security shares	Dec. 31, 2019 USD ($) security
Schedule of Investments [Line Items]
Number of securities in unrealized losses less than twelve months category | security	3
Number of securities in unrealized losses twelve months or more category | security	6
Unrealized (loss) gain on equity securities | $	$ (36)	$ 36
Municipal bonds [Member] | Securities Pledged As Collateral Agreement With Federal Reserve Bank Of New York [Member]
Schedule of Investments [Line Items]
Investment owned balance, positions | security	32		33
Investment owned, at cost | $	$ 10,800		$ 10,900
Investment owned, at fair value | $	$ 11,100		$ 11,200
Municipal bonds [Member] | SecuritiesPledged As Collateral For Customer Deposits [Member]
Schedule of Investments [Line Items]
Investment owned balance, positions | security	16		16
Investment owned, at cost | $	$ 3,600		$ 3,600
Investment owned, at fair value | $	$ 3,700		$ 3,700
Debt Securities [Member]
Schedule of Investments [Line Items]
Number of securities sold | security	0	0
Equity Securities [Member]
Schedule of Investments [Line Items]
Number of securities sold | security	0	0
Unrealized (loss) gain on equity securities | $	$ (36)	$ 36
Equity Securities [Member] | Federal Home Loan Mortgage Corporation [Member]
Schedule of Investments [Line Items]
Equity securities common stock shares owned | shares	22,368	22,368