LOANS AND CREDIT QUALITY - Loan Modifications (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Consumer loans \| Single family \| Significant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 847	$ 682	$ 847	$ 1,209
% of Total Class of Financing Receivable	0.08%	0.08%	0.08%	0.13%
Consumer loans \| Single family \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 273	$ 0	$ 273	$ 270
% of Total Class of Financing Receivable	0.02%	0.00%	0.02%	0.03%
Consumer loans \| Single family \| Interest Rate Reduction and Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 0	$ 477	$ 0	$ 477
% of Total Class of Financing Receivable	0.00%	0.13%	0.00%	0.13%
Consumer loans \| Single family \| Interest Rate Reduction and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 0	$ 0	$ 0	$ 819
% of Total Class of Financing Receivable	0.00%	0.00%	0.00%	0.09%
Consumer loans \| Single family \| Significant Payment Delay and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 1,167	$ 4,033	$ 2,284	$ 13,325
% of Total Class of Financing Receivable	0.11%	0.44%	0.21%	1.47%
Consumer loans \| Single family \| Interest Rate Reduction, Significant Payment Delay and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 0	$ 294	$ 192	$ 7,185
% of Total Class of Financing Receivable	0.00%	0.03%	0.02%	0.79%
Consumer loans \| Home equity and other \| Significant Payment Delay
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 0	$ 0	$ 0	$ 70
% of Total Class of Financing Receivable	0.00%	0.00%	0.00%	0.02%
Consumer loans \| Home equity and other \| Significant Payment Delay and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 0	$ 0	$ 0	$ 51
% of Total Class of Financing Receivable	0.00%	0.00%	0.00%	0.01%
Commercial loans, adjusted for credit analysis \| Non-owner occupied CRE \| Significant Payment Delay and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 16,440	$ 0	$ 16,440	$ 0
% of Total Class of Financing Receivable	2.60%	0.00%	2.60%	0.00%
Commercial loans, adjusted for credit analysis \| CRE construction \| Significant Payment Delay and Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 3,871	$ 0	$ 3,871	$ 0
% of Total Class of Financing Receivable	0.68%	0.00%	0.68%	0.00%
Commercial loans, adjusted for credit analysis \| Commercial business \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized Cost Basis at Period End	$ 9,663	$ 0	$ 10,396	$ 1,570
% of Total Class of Financing Receivable	2.51%	0.00%	2.70%	0.43%

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- Definition

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+ References

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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

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