LOANS AND CREDIT QUALITY - Activity in Allowance for Credit Losses by Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Allowance for credit losses by loan portfolio
Beginning balance	$ 41,500	$ 37,355	$ 41,500	$ 47,123
Charge-offs	(635)	(124)	(1,574)	(850)
Recoveries	125	126	364	523
Provision	(990)	249	(290)	(9,190)
Ending balance	40,000	37,606	40,000	37,606
Commercial and industrial loans \| Real Estate Sector
Allowance for credit losses by loan portfolio
Beginning balance	26,160	24,851	27,859	21,486
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(608)	(33)	(2,307)	3,332
Ending balance	25,552	24,818	25,552	24,818
Commercial and industrial loans \| Commercial and Industrial Sector
Allowance for credit losses by loan portfolio
Beginning balance	4,767	4,670	4,277	17,279
Charge-offs	(543)	(81)	(1,342)	(741)
Recoveries	25	25	73	94
Provision	454	74	1,695	(11,944)
Ending balance	4,703	4,688	4,703	4,688
Commercial and industrial loans \| Non-owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	2,242	2,180	2,102	7,509
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	123	(74)	263	(5,403)
Ending balance	2,365	2,106	2,365	2,106
Commercial and industrial loans \| Multifamily
Allowance for credit losses by loan portfolio
Beginning balance	9,695	10,074	10,974	5,854
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	1,011	1,109	(268)	5,329
Ending balance	10,706	11,183	10,706	11,183
Commercial and industrial loans \| Multifamily construction
Allowance for credit losses by loan portfolio
Beginning balance	1,566	566	998	507
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	26	99	594	158
Ending balance	1,592	665	1,592	665
Commercial and industrial loans \| CRE construction
Allowance for credit losses by loan portfolio
Beginning balance	169	185	196	150
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(16)	(25)	(43)	10
Ending balance	153	160	153	160
Commercial and industrial loans \| Single family construction
Allowance for credit losses by loan portfolio
Beginning balance	11,067	10,687	12,418	6,411
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(1,322)	(1,123)	(2,673)	3,153
Ending balance	9,745	9,564	9,745	9,564
Commercial and industrial loans \| Single family construction to permanent
Allowance for credit losses by loan portfolio
Beginning balance	1,421	1,159	1,171	1,055
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(430)	(19)	(180)	85
Ending balance	991	1,140	991	1,140
Commercial and industrial loans \| Owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	930	1,092	1,030	5,006
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	172	(123)	72	(4,037)
Ending balance	1,102	969	1,102	969
Commercial and industrial loans \| Commercial business
Allowance for credit losses by loan portfolio
Beginning balance	3,837	3,578	3,247	12,273
Charge-offs	(543)	(81)	(1,342)	(741)
Recoveries	25	25	73	94
Provision	282	197	1,623	(7,907)
Ending balance	3,601	3,719	3,601	3,719
Consumer loans
Allowance for credit losses by loan portfolio
Beginning balance	10,573	7,834	9,364	8,358
Charge-offs	(92)	(43)	(232)	(109)
Recoveries	100	101	291	429
Provision	(836)	208	322	(578)
Ending balance	9,745	8,100	9,745	8,100
Consumer loans \| Single family
Allowance for credit losses by loan portfolio
Beginning balance	6,617	4,027	5,610	4,394
Charge-offs	0	0	0	0
Recoveries	4	1	21	141
Provision	(838)	436	152	(71)
Ending balance	5,783	4,464	5,783	4,464
Consumer loans \| Home equity and other
Allowance for credit losses by loan portfolio
Beginning balance	3,956	3,807	3,754	3,964
Charge-offs	(92)	(43)	(232)	(109)
Recoveries	96	100	270	288
Provision	2	(228)	170	(507)
Ending balance	$ 3,962	$ 3,636	$ 3,962	$ 3,636

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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+ 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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