FAIR VALUE DISCLOSURES AND REPORTING, THE FAIR VALUE OPTION AND FAIR VALUE MEASUREMENTS - Reconciliation of Activity for Assets Measured at Fair Value based on Significant Unobservable (Non-market) Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Bank-Issued Trust Preferred Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, January 1	$ 31	$ 43
Paydowns	0	(11)
Balance at September 30	31	32
Municipal securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, January 1	15,117	20,123
Purchases	0	0
Maturities, calls and paydowns	(532)	(524)
Transfer from level 2 to level 3	6,085	0
Unrealized gain (loss) included in comprehensive income	(1,177)	(2,641)
Balance at September 30	$ 19,493	$ 16,958