Securities Available for Sale (Schedule of Contractual Maturity of Debt Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Contractual maturity of debt securities, Amortized Cost
Due in one year or less	$ 13,125
Due after one year through five years	131,284
Due after five years through ten years	54,955
Due after ten years	116,469
Total debt securities	315,833
Contractual maturity of debt securities, Fair Value
Due in one year or less	12,726
Due after one year through five years	127,386
Due after five years through ten years	52,891
Due after ten years	114,250
Securities available for sale	$ 307,253	$ 314,078	$ 311,214

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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