LOANS AND ALLOWANCE FOR CREDIT LOSSES - Schedule of Changes in the ACL (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2026	Jun. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 43,660	$ 43,666	$ 51,014	$ 43,888	$ 47,729	$ 47,729
Provision for/(reversal of) credit losses	500	77	750	377	9,983
Charge-offs	(137)	(119)	(7,019)	(283)	(13,084)	(14,712)
Recoveries	15	36	147	56	264
Ending balance	44,038	43,660	44,892	44,038	44,892	43,888
Single-family residential mortgages
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	21,766	21,988	19,106	21,585	17,518	17,518
Provision for/(reversal of) credit losses	4	(222)	2,737	185	5,728
Charge-offs	0	0	0	0	(1,403)	(1,403)
Recoveries	0	0	0	0	0
Ending balance	21,770	21,766	21,843	21,770	21,843	21,585
Commercial real estate
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	17,527	17,639	21,423	18,162	21,879	21,879
Provision for/(reversal of) credit losses	293	(139)	(2,730)	(369)	89
Charge-offs	0	0	(21)	0	(3,296)	(4,679)
Recoveries	0	27	0	27	0
Ending balance	17,820	17,527	18,672	17,820	18,672	18,162
Construction and land development
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,954	1,446	7,971	1,502	6,053	6,053
Provision for/(reversal of) credit losses	79	508	312	531	3,476
Charge-offs	0	0	(6,929)	0	(8,175)	(8,175)
Recoveries	0	0	138	0	138
Ending balance	2,033	1,954	1,492	2,033	1,492	1,502
Commercial and industrial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,593	1,672	1,493	1,647	1,339	1,339
Provision for/(reversal of) credit losses	132	23	393	183	550
Charge-offs	(107)	(102)	(4)	(213)	(85)	(88)
Recoveries	1	0	1	2	79
Ending balance	1,619	1,593	1,883	1,619	1,883	1,647
SBA
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	689	769	791	824	654	654
Provision for/(reversal of) credit losses	(11)	(80)	19	(144)	157
Charge-offs	0	0	(11)	(2)	(12)	(187)
Recoveries	1	0	0	1	0
Ending balance	679	689	799	679	799	824
Other
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	131	152	230	168	286	286
Provision for/(reversal of) credit losses	3	(13)	19	(9)	(17)
Charge-offs	(30)	(17)	(54)	(68)	(113)	(180)
Recoveries	13	9	8	26	47
Ending balance	117	131	203	117	203	168
Reserve for unfunded loan commitments
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	407	484	629	484	729	729
Provision for/(reversal of) credit losses	0	(77)	(125)	(77)	(225)
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Ending balance	407	407	504	407	504	484
Allowance for credit losses
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	44,067	44,150	51,643	44,372	48,458	48,458
Provision for/(reversal of) credit losses	500	0	625	300	9,758
Charge-offs	(137)	(119)	(7,019)	(283)	(13,084)
Recoveries	15	36	147	56	264
Ending balance	$ 44,445	$ 44,067	$ 45,396	$ 44,445	$ 45,396	$ 44,372

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
-Paragraph 13
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
-Paragraph 13
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