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, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Allowance for credit losses by loan portfolio
Beginning balance	$ 37,606	$ 54,516	$ 37,606	$ 54,516	$ 37,355	$ 47,123	$ 59,897	$ 64,294
Charge-offs	(124)	(470)	(850)	(675)
Recoveries	126	437	523	761
Provision	249	(5,348)	(9,190)	(9,864)
Ending balance	37,606	54,516	37,606	54,516
Commercial loans \| Real Estate Sector
Allowance for credit losses by loan portfolio
Beginning balance	24,818	23,841	24,818	23,841	24,851	21,486	25,544	27,935
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(33)	(1,703)	3,332	(4,094)
Ending balance	24,818	23,841	24,818	23,841
Commercial loans \| Commercial and Industrial Sector
Allowance for credit losses by loan portfolio
Beginning balance	4,688	19,758	4,688	19,758	4,670	17,279	21,392	22,037
Charge-offs	(81)	(116)	(741)	(116)
Recoveries	25	24	94	122
Provision	74	(1,542)	(11,944)	(2,285)
Ending balance	4,688	19,758	4,688	19,758
Commercial loans \| Non-owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	2,106	9,636	2,106	9,636	2,180	7,509	9,077	8,845
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(74)	559	(5,403)	791
Ending balance	2,106	9,636	2,106	9,636
Commercial loans \| Multifamily
Allowance for credit losses by loan portfolio
Beginning balance	11,183	5,457	11,183	5,457	10,074	5,854	7,245	6,072
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	1,109	(1,788)	5,329	(615)
Ending balance	11,183	5,457	11,183	5,457
Commercial loans \| Multifamily construction
Allowance for credit losses by loan portfolio
Beginning balance	665	1,044	665	1,044	566	507	500	4,903
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	99	544	158	(3,859)
Ending balance	665	1,044	665	1,044
Commercial loans \| CRE construction
Allowance for credit losses by loan portfolio
Beginning balance	160	351	160	351	185	150	2,022	1,670
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(25)	(1,671)	10	(1,319)
Ending balance	160	351	160	351
Commercial loans \| Single family construction
Allowance for credit losses by loan portfolio
Beginning balance	9,564	6,291	9,564	6,291	10,687	6,411	5,653	5,130
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(1,123)	638	3,153	1,161
Ending balance	9,564	6,291	9,564	6,291
Commercial loans \| Single family construction to permanent
Allowance for credit losses by loan portfolio
Beginning balance	1,140	1,062	1,140	1,062	1,159	1,055	1,047	1,315
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(19)	15	85	(253)
Ending balance	1,140	1,062	1,140	1,062
Commercial loans \| Owner occupied CRE
Allowance for credit losses by loan portfolio
Beginning balance	969	5,285	969	5,285	1,092	5,006	5,518	4,994
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(123)	(233)	(4,037)	291
Ending balance	969	5,285	969	5,285
Commercial loans \| Commercial business
Allowance for credit losses by loan portfolio
Beginning balance	3,719	14,473	3,719	14,473	3,578	12,273	15,874	17,043
Charge-offs	(81)	(116)	(741)	(116)
Recoveries	25	24	94	122
Provision	197	(1,309)	(7,907)	(2,576)
Ending balance	3,719	14,473	3,719	14,473
Consumer loans
Allowance for credit losses by loan portfolio
Beginning balance	8,100	10,917	8,100	10,917	7,834	8,358	12,961	14,322
Charge-offs	(43)	(354)	(109)	(559)
Recoveries	101	413	429	639
Provision	208	(2,103)	(578)	(3,485)
Ending balance	8,100	10,917	8,100	10,917
Consumer loans \| Single family
Allowance for credit losses by loan portfolio
Beginning balance	4,464	5,757	4,464	5,757	4,027	4,394	7,163	6,906
Charge-offs	0	(13)	0	(127)
Recoveries	1	33	141	155
Provision	436	(1,426)	(71)	(1,177)
Ending balance	4,464	5,757	4,464	5,757
Consumer loans \| Home equity and other
Allowance for credit losses by loan portfolio
Beginning balance	3,636	5,160	3,636	5,160	$ 3,807	$ 3,964	$ 5,798	$ 7,416
Charge-offs	(43)	(341)	(109)	(432)
Recoveries	100	380	288	484
Provision	(228)	(677)	(507)	(2,308)
Ending balance	$ 3,636	$ 5,160	$ 3,636	$ 5,160

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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