LOANS AND CREDIT QUALITY - Activity in Allowance for Credit Losses by Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allowance for credit losses by loan portfolio
Beginning balance	$ 41,500	$ 37,944	$ 41,500	$ 47,123
Charge-offs	(256)	(682)	(939)	(726)
Recoveries	145	309	239	397
Provision	111	(216)	700	(9,439)
Ending balance	41,500	37,355	41,500	37,355
Commercial and industrial loans \| Real Estate Sector
Allowance for credit losses by loan portfolio
Beginning balance	27,680	20,086	27,859	21,486
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(1,520)	4,765	(1,699)	3,365
Ending balance	26,160	24,851	26,160	24,851
Commercial and industrial loans \| Commercial and Industrial Sector
Allowance for credit losses by loan portfolio
Beginning balance	4,326	10,446	4,277	17,279
Charge-offs	(166)	(649)	(799)	(660)
Recoveries	24	45	48	69
Provision	583	(5,172)	1,241	(12,018)
Ending balance	4,767	4,670	4,767	4,670
Commercial and industrial loans \| Non-owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	2,608	2,294	2,102	7,509
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(366)	(114)	140	(5,329)
Ending balance	2,242	2,180	2,242	2,180
Commercial and industrial loans \| Multifamily
Allowance for credit losses by loan portfolio
Beginning balance	9,787	8,427	10,974	5,854
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(92)	1,647	(1,279)	4,220
Ending balance	9,695	10,074	9,695	10,074
Commercial and industrial loans \| Multifamily construction
Allowance for credit losses by loan portfolio
Beginning balance	1,345	456	998	507
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	221	110	568	59
Ending balance	1,566	566	1,566	566
Commercial and industrial loans \| CRE construction
Allowance for credit losses by loan portfolio
Beginning balance	204	184	196	150
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(35)	1	(27)	35
Ending balance	169	185	169	185
Commercial and industrial loans \| Single family construction
Allowance for credit losses by loan portfolio
Beginning balance	12,525	7,735	12,418	6,411
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(1,458)	2,952	(1,351)	4,276
Ending balance	11,067	10,687	11,067	10,687
Commercial and industrial loans \| Single family construction to permanent
Allowance for credit losses by loan portfolio
Beginning balance	1,211	990	1,171	1,055
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	210	169	250	104
Ending balance	1,421	1,159	1,421	1,159
Commercial and industrial loans \| Owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	910	3,536	1,030	5,006
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	20	(2,444)	(100)	(3,914)
Ending balance	930	1,092	930	1,092
Commercial and industrial loans \| Commercial business
Allowance for credit losses by loan portfolio
Beginning balance	3,416	6,910	3,247	12,273
Charge-offs	(166)	(649)	(799)	(660)
Recoveries	24	45	48	69
Provision	563	(2,728)	1,341	(8,104)
Ending balance	3,837	3,578	3,837	3,578
Consumer loans
Allowance for credit losses by loan portfolio
Beginning balance	9,494	7,412	9,364	8,358
Charge-offs	(90)	(33)	(140)	(66)
Recoveries	121	264	191	328
Provision	1,048	191	1,158	(786)
Ending balance	10,573	7,834	10,573	7,834
Consumer loans \| Single family
Allowance for credit losses by loan portfolio
Beginning balance	5,804	3,762	5,610	4,394
Charge-offs	0	0	0	0
Recoveries	2	136	17	140
Provision	811	129	990	(507)
Ending balance	6,617	4,027	6,617	4,027
Consumer loans \| Home equity and other
Allowance for credit losses by loan portfolio
Beginning balance	3,690	3,650	3,754	3,964
Charge-offs	(90)	(33)	(140)	(66)
Recoveries	119	128	174	188
Provision	237	62	168	(279)
Ending balance	$ 3,956	$ 3,807	$ 3,956	$ 3,807

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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