INVESTMENT SECURITIES - Summary of Amortized Cost and Fair Value - Held-To-Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Amortized Cost
Due in one year or less	$ 766
Due after one year through five years	1,211
Mortgage-backed securities	35,782
Amortized Cost	37,759	$ 81,052
Fair Value
Due in one year or less	766
Due after one year through five years	1,202
Mortgage-backed securities	35,006
Fair Value	$ 36,974	$ 80,920

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

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