LOANS AND CREDIT QUALITY - TDRs (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	27	43	143
Recorded investment - TDR	$ 8,297	$ 10,477	$ 40,610
Related charge-offs - TDR	$ 0	$ 0	$ 0
Consumer loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	27	41	140
Recorded investment - TDR	$ 8,297	$ 8,674	$ 29,836
Related charge-offs - TDR	$ 0	$ 0	$ 0
Commercial and Industrial Sector \| Commercial loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		2	2
Recorded investment - TDR		$ 1,803	$ 6,099
Related charge-offs - TDR		$ 0	$ 0
Payment restructure
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	7	16	122
Recorded investment - TDR	$ 2,815	$ 4,498	$ 36,685
Related charge-offs - TDR	$ 0	$ 0	$ 0
Payment restructure \| Commercial loans \| Construction/land development
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan			1
Recorded investment - TDR			$ 4,675
Related charge-offs - TDR			$ 0
Payment restructure \| Commercial loans \| Owner occupied CRE
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		1	1
Recorded investment - TDR		$ 678	$ 5,840
Related charge-offs - TDR		$ 0	$ 0
Payment restructure \| Commercial loans \| Commercial business
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		1	1
Recorded investment - TDR		$ 1,125	$ 259
Related charge-offs - TDR		$ 0	$ 0
Payment restructure \| Consumer loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan			119
Recorded investment - TDR			$ 25,911
Related charge-offs - TDR			$ 0
Payment restructure \| Consumer loans \| Single family
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	7	14	118
Recorded investment - TDR	$ 2,815	$ 2,695	$ 25,795
Related charge-offs - TDR	$ 0	$ 0	$ 0
Payment restructure \| Consumer loans \| Home equity and other
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan			1
Recorded investment - TDR			$ 116
Related charge-offs - TDR			$ 0
Payment restructure \| Real Estate Sector \| Commercial loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan			1
Recorded investment - TDR			$ 4,675
Related charge-offs - TDR			$ 0
Payment restructure \| Commercial and Industrial Sector \| Commercial loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan		2	2
Recorded investment - TDR		$ 1,803	$ 6,099
Related charge-offs - TDR		$ 0	$ 0
Interest rate reduction
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	20	27	21
Recorded investment - TDR	$ 5,482	$ 5,979	$ 3,925
Related charge-offs - TDR	$ 0	$ 0	$ 0
Interest rate reduction \| Consumer loans
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan			21
Recorded investment - TDR			$ 3,925
Related charge-offs - TDR			$ 0
Interest rate reduction \| Consumer loans \| Single family
Financing Receivable, Impaired [Line Items]
Number of loan modifications - TDR \| loan	20	27	21
Recorded investment - TDR	$ 5,482	$ 5,979	$ 3,925
Related charge-offs - TDR	$ 0	$ 0	$ 0

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+ References

No definition available.

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 310
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