SECURITIES - Amortized Cost and Fair Value of Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Amortized Cost
Due in one year or less	$ 10,879
Due after one year through five years	65,441
Due after five years through ten years	100,154
Due after ten years	115,780
Subtotal	292,254
Agency mortgage-backed pass through securities	30,183
Total	322,437
Fair Value
Due in one year or less	10,904
Due after one year through five years	65,873
Due after five years through ten years	100,909
Due after ten years	116,038
Subtotal	293,724
Agency mortgage-backed pass through securities	30,132
Total	$ 323,856	$ 316,455