Securities (Schedule of Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Securities Available-for-Sale: Amortized cost
Due in one year or less	$ 2,206
Due after one year through five years	16,102
Due after five years through ten years	76,237
Due after ten years	189,347
Amortized Cost	821,194	$ 821,254
Securities Available-for-Sale: Fair Value
Due in one year or less	2,216
Due after one year through five years	16,431
Due after five years through ten years	78,748
Due after ten years	194,922
Fair Value	824,597	812,611
MBS/CMO - Residential
Securities Available-for-Sale: Amortized cost
Amortized cost, MBS/CMO - Residential	537,302
Amortized Cost	537,302	529,805
Securities Available-for-Sale: Fair Value
Fair value, MBS/CMO - Residential	532,280
Fair Value	$ 532,280	$ 518,078

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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