Securities (Schedule of Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Securities Available-for-Sale: Amortized cost
Due in one year or less	$ 2,588
Due after one year through five years	21,074
Due after five years through ten years	75,427
Due after ten years	178,046
Amortized Cost	756,118	$ 743,642
Securities Available-for-Sale: Fair Value
Due in one year or less	2,602
Due after one year through five years	21,560
Due after five years through ten years	76,655
Due after ten years	178,020
Fair Value	739,481	740,641
MBS/CMO - Residential
Securities Available-for-Sale: Amortized cost
Amortized cost, MBS/CMO - Residential	478,983
Amortized Cost	478,983	476,205
Securities Available-for-Sale: Fair Value
Fair value, MBS/CMO - Residential	460,644
Fair Value	$ 460,644	$ 467,332

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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