LOANS AND CREDIT QUALITY - TDRs (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan	Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	5	10	7	26
Recorded investment - TDR	$ 1,947	$ 2,225	$ 2,455	$ 6,695
Related charge-offs - TDR	$ 0	$ 0	$ 0	$ 0
Consumer loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		10		24
Recorded investment - TDR		$ 2,225		$ 4,892
Related charge-offs - TDR		$ 0		$ 0
Consumer loans \| Single family
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	5		7
Recorded investment - TDR	$ 1,947		$ 2,455
Related charge-offs - TDR	$ 0		$ 0
Commercial and Industrial Sector \| Commercial loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		0		2
Recorded investment - TDR		$ 0		$ 1,803
Related charge-offs - TDR		$ 0		$ 0
Interest rate reduction
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	3	4	5	15
Recorded investment - TDR	$ 807	$ 1,023	$ 1,315	$ 3,236
Related charge-offs - TDR	$ 0	$ 0	$ 0	$ 0
Interest rate reduction \| Consumer loans \| Single family
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	3	4	5	15
Recorded investment - TDR	$ 807	$ 1,023	$ 1,315	$ 3,236
Related charge-offs - TDR	$ 0	$ 0	$ 0	$ 0
Payment restructure
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	2	6	2	11
Recorded investment - TDR	$ 1,140	$ 1,202	$ 1,140	$ 3,459
Related charge-offs - TDR	$ 0	$ 0	$ 0	$ 0
Payment restructure \| Commercial loans \| Owner occupied commercial real estate
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		0		1
Recorded investment - TDR		$ 0		$ 678
Related charge-offs - TDR		$ 0		$ 0
Payment restructure \| Commercial loans \| Commercial business
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		0		1
Recorded investment - TDR		$ 0		$ 1,125
Related charge-offs - TDR		$ 0		$ 0
Payment restructure \| Consumer loans \| Single family
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	2	6	2	9
Recorded investment - TDR	$ 1,140	$ 1,202	$ 1,140	$ 1,656
Related charge-offs - TDR	$ 0	$ 0		$ 0
Payment restructure \| Commercial and Industrial Sector \| Commercial loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		0		2
Recorded investment - TDR		$ 0		$ 1,803
Related charge-offs - TDR		$ 0		$ 0

Financing Receivable, Modifications, Recorded Investment at Period End

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+ References

No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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