INVESTMENT SECURITIES - Schedule of Investment Securities Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized Cost
Five to ten years	$ 3,596
Beyond ten years	12,084
Amortized Cost	626,064	$ 623,037
Fair Value
Five to ten years	3,588
Beyond ten years	12,108
Fair Value	635,324	625,074
Amortized Cost
Held-to-maturity investment securities beyond ten years	79
Amortized Cost	9,400	10,170
Fair Value
Beyond ten years	79
Total held to maturity debt securities	9,839	$ 10,349
MBS and CMOs
Amortized Cost
MBS and CMOs	610,384
Fair Value
MBS and CMOs	619,628
MBS
Amortized Cost
MBS	9,321
Fair Value
MBS	$ 9,760