INVESTMENT SECURITIES - Schedule of contractual maturity of Held to Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Held to Maturity, Amortized Cost
Within one year	$ 25	$ 0
One to five years	0	25
Five to ten years	0	0
Due after ten years	4,732	5,403
Amortized Cost, total	4,757	5,428
Held to Maturity, Amortized Cost	4,757	5,428
Held to Maturity, Fair Value
Within one year	25	0
One to five years	0	25
Five to ten years	0	0
Due after ten years	4,504	5,305
Fair Value, total	4,529	5,330
Held to Maturity, Fair Value	4,529	5,330
Residential mortgage-backed securities
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost	4,732	5,403
Held to Maturity, Fair Value
Held to Maturity, Fair Value	$ 4,504	$ 5,305

Amount of investment in debt security measured at amortized cost (held-to-maturity).

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