Investment Securities (Schedule of contractual maturity of available for sale investment securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available for Sale: Amortized Cost
Within One Year
After One Year Through Five Years	114
After Five Years Through Ten Years	1,388
After Ten Years	4,680
Amortized Cost	6,182	$ 4,260
Available for Sale: Fair Value
Within One Year
After One Year Through Five Years	114
After Five Years Through Ten Years	1,394
After Ten Years	4,702
Fair Value	$ 6,210	$ 4,221

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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