LOANS AND CREDIT QUALITY - Loan Modifications, Financial Effect (Details)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Commercial business \| Commercial business
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average contractual interest rate, before modification		5.72%
Weighted average contractual interest rate, after modification		4.00%
Commercial business \| Commercial business \| Significant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)	5 years 2 months 12 days
Commercial business \| Commercial business \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)	1 year 2 months 12 days	9 months 18 days
Commercial business \| Non-owner occupied CRE \| Significant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)	3 years 8 months 12 days
Commercial business \| Non-owner occupied CRE \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)	2 years 1 month 6 days
Commercial business \| CRE construction \| Significant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)	2 years 8 months 12 days
Commercial business \| CRE construction \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)	1 year 7 months 6 days
Commercial business \| Home equity and other \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)		16 years 1 month 6 days
Consumer loans \| Single family \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average contractual interest rate, before modification	5.25%	4.25%
Weighted average contractual interest rate, after modification	5.00%	3.31%
Consumer loans \| Single family \| Significant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average percent of loan balances capitalized and added to term of loan	0.37%	0.22%
Consumer loans \| Single family \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average time added to life of loans (in years)	4 years 10 months 24 days	4 years 4 months 24 days
Consumer loans \| Home equity and other \| Significant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted average percent of loan balances capitalized and added to term of loan		3.47%

Financing Receivable, Loan Modifications, Weighted Average Percent Of Loan Capitalized

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- Definition

Financing Receivable, Weighted Average Interest Rate, After Loan Modification

+ References

No definition available.

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- Definition

Financing Receivable, Weighted Average Interest Rate, Before Loan Modification

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

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- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

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