INVESTMENT SECURITIES - Amortized Cost and Fair Values of AFS Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025	Sep. 30, 2025
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	$ 985,444	$ 972,138
Gross Unrealized Gains	630	7,948
(Gross Unrealized Losses)	66,626	27,346
Allowance for Credit Losses	0	0
Fair Value	919,448	952,740	$ 41,600
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	15,010	15,016
Gross Unrealized Gains	0	0
(Gross Unrealized Losses)	844	805
Allowance for Credit Losses	0	0
Fair Value	14,166	14,211
U.S. Government Agencies
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	1,325	1,746
Gross Unrealized Gains	35	50
(Gross Unrealized Losses)	0	0
Allowance for Credit Losses	0	0
Fair Value	1,360	1,796
States and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	217,801	218,832
Gross Unrealized Gains	0	288
(Gross Unrealized Losses)	30,484	16,972
Allowance for Credit Losses	0	0
Fair Value	187,317	202,148
GSE residential MBSs
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	249,039	234,016
Gross Unrealized Gains	0	3,228
(Gross Unrealized Losses)	17,448	3,141
Allowance for Credit Losses	0	0
Fair Value	231,591	234,103
GSE commercial MBSs
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	10,813	6,081
Gross Unrealized Gains	19	106
(Gross Unrealized Losses)	394	16
Allowance for Credit Losses	0	0
Fair Value	10,438	6,171
GSE residential CMOs
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	340,352	354,954
Gross Unrealized Gains	255	3,425
(Gross Unrealized Losses)	13,697	4,376
Allowance for Credit Losses	0	0
Fair Value	326,910	354,003
Non-agency CMOs
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	80,030	60,693
Gross Unrealized Gains	12	363
(Gross Unrealized Losses)	3,084	1,233
Allowance for Credit Losses	0	0
Fair Value	76,958	59,823
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	69,804	78,610
Gross Unrealized Gains	305	443
(Gross Unrealized Losses)	675	803
Allowance for Credit Losses	0	0
Fair Value	69,434	78,250
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	957	1,947
Gross Unrealized Gains	4	45
(Gross Unrealized Losses)	0	0
Allowance for Credit Losses	0	0
Fair Value	961	1,992
Other
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, amortized cost	313	243
Gross Unrealized Gains	0	0
(Gross Unrealized Losses)	0	0
Allowance for Credit Losses	0	0
Fair Value	$ 313	$ 243

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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