LOANS AND CREDIT QUALITY - Activity in Allowance for Credit Losses by Loan Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for credit losses by loan portfolio
Beginning balance	$ 41,500	$ 47,123	$ 64,294
Charge-offs	(1,381)	(1,266)	(2,349)
Recoveries	448	638	994
Provision	(67)	(4,995)	(15,816)
Ending balance	40,500	41,500	47,123
Commercial and industrial loans \| Real Estate Sector
Allowance for credit losses by loan portfolio
Beginning balance	27,859	21,486	27,935
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	53	6,373	(6,449)
Ending balance	27,912	27,859	21,486
Commercial and industrial loans \| Commercial and Industrial Sector
Allowance for credit losses by loan portfolio
Beginning balance	4,277	17,279	22,037
Charge-offs	(1,062)	(1,098)	(1,739)
Recoveries	87	163	146
Provision	547	(12,067)	(3,165)
Ending balance	3,849	4,277	17,279
Commercial and industrial loans \| Non-owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	2,102	7,509	8,845
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	508	(5,407)	(1,336)
Ending balance	2,610	2,102	7,509
Commercial and industrial loans \| Multifamily
Allowance for credit losses by loan portfolio
Beginning balance	10,974	5,854	6,072
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	2,119	5,120	(218)
Ending balance	13,093	10,974	5,854
Commercial and industrial loans \| Multifamily construction
Allowance for credit losses by loan portfolio
Beginning balance	998	507	4,903
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	2,985	491	(4,396)
Ending balance	3,983	998	507
Commercial and industrial loans \| CRE construction
Allowance for credit losses by loan portfolio
Beginning balance	196	150	1,670
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	(7)	46	(1,520)
Ending balance	189	196	150
Commercial and industrial loans \| Single family construction
Allowance for credit losses by loan portfolio
Beginning balance	12,418	6,411	5,130
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	(5,053)	6,007	1,281
Ending balance	7,365	12,418	6,411
Commercial and industrial loans \| Single family construction to permanent
Allowance for credit losses by loan portfolio
Beginning balance	1,171	1,055	1,315
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	(499)	116	(260)
Ending balance	672	1,171	1,055
Commercial and industrial loans \| Owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	1,030	5,006	4,994
Charge-offs	0		0
Recoveries	0	0	0
Provision	(131)	(3,976)	12
Ending balance	899	1,030	5,006
Commercial and industrial loans \| Commercial business
Allowance for credit losses by loan portfolio
Beginning balance	3,247	12,273	17,043
Charge-offs	(1,062)	(1,098)	(1,739)
Recoveries	87	163	146
Provision	678	(8,091)	(3,177)
Ending balance	2,950	3,247	12,273
Consumer loans
Allowance for credit losses by loan portfolio
Beginning balance	9,364	8,358	14,322
Charge-offs	(319)	(168)	(610)
Recoveries	361	475	848
Provision	(667)	699	(6,202)
Ending balance	8,739	9,364	8,358
Consumer loans \| Single family
Allowance for credit losses by loan portfolio
Beginning balance	5,610	4,394	6,906
Charge-offs	0	0	(127)
Recoveries	23	143	291
Provision	(346)	1,073	(2,676)
Ending balance	5,287	5,610	4,394
Consumer loans \| Home equity and other
Allowance for credit losses by loan portfolio
Beginning balance	3,754	3,964	7,416
Charge-offs	(319)	(168)	(483)
Recoveries	338	332	557
Provision	(321)	(374)	(3,526)
Ending balance	$ 3,452	$ 3,754	$ 3,964

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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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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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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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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