SECURITIES - Additional Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017 security	Dec. 31, 2023 USD ($) segment security	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Securities pledged as collateral		$ 992,100	$ 946,300
Gain on sale of investments		1	6	$ 274
Loss on sale of investments		$ 2	3	160
Number of CDO other-than-temporary impaired | security		3
Number of CDO called | security	1
Number of investment securities segregation for impairment evaluation | segment		2
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | segment		844
Cumulative credit loss charges recorded through earnings to date		$ 2,974	2,974	$ 2,974	$ 2,974
Unrealized losses		157,845	$ 172,134
Collateralized debt obligations
Debt Securities, Available-for-sale [Line Items]
Contractual balance		3,700
Reduced balance		3,000
Interest payment received		750
Other comprehensive income net		3,000
Cumulative credit loss charges recorded through earnings to date		$ 3,000