INVESTMENT SECURITIES - Amortized Cost and Fair Values of AFS Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 845,869	$ 549,089
Gross Unrealized Gains	9,513	1,317
Gross Unrealized Losses	28,554	36,887
Allowance for Credit Losses	0	0
Fair Value	826,828	513,519
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	20,047	20,057
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,674	2,217
Allowance for Credit Losses	0	0
Fair Value	18,373	17,840	$ 19,900
U.S. Government Agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,249	3,994
Gross Unrealized Gains	123	157
Gross Unrealized Losses	0	0
Allowance for Credit Losses	0	0
Fair Value	3,372	4,151
States and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	220,909	221,624
Gross Unrealized Gains	301	28
Gross Unrealized Losses	15,110	18,530
Allowance for Credit Losses	0	0
Fair Value	206,100	203,122
GSE residential MBSs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	149,806	61,669
Gross Unrealized Gains	3,378	0
Gross Unrealized Losses	2,823	4,037
Allowance for Credit Losses	0	0
Fair Value	150,361	57,632
GSE commercial MBSs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,164	4,387
Gross Unrealized Gains	461	356
Gross Unrealized Losses	1	0
Allowance for Credit Losses	0	0
Fair Value	9,624	4,743
GSE residential CMOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	314,857	79,284
Gross Unrealized Gains	4,349	18
Gross Unrealized Losses	5,081	6,200
Allowance for Credit Losses	0	0
Fair Value	314,125	73,102
Non-agency CMOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	33,698	48,162
Gross Unrealized Gains	306	316
Gross Unrealized Losses	2,772	3,809
Allowance for Credit Losses	0	0
Fair Value	31,232	44,669
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	92,009	109,786
Gross Unrealized Gains	552	442
Gross Unrealized Losses	1,093	2,094
Allowance for Credit Losses	0	0
Fair Value	91,468	108,134
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,932
Gross Unrealized Gains	43
Gross Unrealized Losses	0
Allowance for Credit Losses	0
Fair Value	1,975
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	198	126
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Allowance for Credit Losses	0	0
Fair Value	$ 198	$ 126

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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