LOANS AND CREDIT QUALITY - Activity in Allowance for Credit Losses by Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Allowance for credit losses by loan portfolio
Beginning balance	$ 38,743	$ 40,500	$ 40,500
Charge-offs	(61)	(1,105)	(3,141)
Provision	64	40
Provision	888	242
Ending balance	39,634	39,677	38,743
Commercial and industrial loans \| Real Estate Sector
Allowance for credit losses by loan portfolio
Beginning balance	24,484	27,912	27,912
Charge-offs	0	0
Provision	0	0
Provision	(3,154)	988
Ending balance	21,330	28,900	24,484
Commercial and industrial loans \| Commercial and Industrial Sector
Allowance for credit losses by loan portfolio
Beginning balance	7,462	3,849	3,849
Charge-offs	(21)	(1,081)
Provision	25	1
Provision	3,780	713
Ending balance	11,246	3,482	7,462
Commercial and industrial loans \| Non-owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	1,739	2,610	2,610
Charge-offs	0	0
Provision	0	0
Provision	(81)	(479)
Ending balance	1,658	2,131	1,739
Commercial and industrial loans \| Multifamily
Allowance for credit losses by loan portfolio
Beginning balance	14,909	13,093	13,093
Charge-offs	0	0
Provision	0	0
Provision	(1,622)	5,854
Ending balance	13,287	18,947	14,909
Commercial and industrial loans \| Multifamily construction
Allowance for credit losses by loan portfolio
Beginning balance	849	3,983	3,983
Charge-offs	0	0
Provision	0	0
Provision	(381)	(2,362)
Ending balance	468	1,621	849
Commercial and industrial loans \| CRE construction
Allowance for credit losses by loan portfolio
Beginning balance	66	189	189
Charge-offs	0	0
Provision	0	0
Provision	7	(1)
Ending balance	73	188	66
Commercial and industrial loans \| Single family construction
Allowance for credit losses by loan portfolio
Beginning balance	6,737	7,365	7,365
Charge-offs	0	0
Provision	0	0
Provision	(1,033)	(1,787)
Ending balance	5,704	5,578	6,737
Commercial and industrial loans \| Single family construction to permanent
Allowance for credit losses by loan portfolio
Beginning balance	184	672	672
Charge-offs	0	0
Provision	0	0
Provision	(44)	(237)
Ending balance	140	435	184
Commercial and industrial loans \| Owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	576	899	899
Charge-offs	0	0
Provision	0	0
Provision	22	(63)
Ending balance	598	836	576
Commercial and industrial loans \| Commercial business
Allowance for credit losses by loan portfolio
Beginning balance	6,886	2,950	2,950
Charge-offs	(21)	(1,081)	(2,963)
Provision	25	1
Provision	3,758	776
Ending balance	10,648	2,646	6,886
Consumer loans
Allowance for credit losses by loan portfolio
Beginning balance	6,797	8,739	8,739
Charge-offs	(40)	(24)
Provision	39	39
Provision	262	(1,459)
Ending balance	7,058	7,295	6,797
Consumer loans \| Single family
Allowance for credit losses by loan portfolio
Beginning balance	3,610	5,287	5,287
Charge-offs	0	0
Provision	2	2
Provision	90	(1,016)
Ending balance	3,702	4,273	3,610
Consumer loans \| Home equity and other
Allowance for credit losses by loan portfolio
Beginning balance	3,187	3,452	3,452
Charge-offs	(40)	(24)	(178)
Provision	37	37
Provision	172	(443)
Ending balance	$ 3,356	$ 3,022	$ 3,187

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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