LOANS AND CREDIT QUALITY - Loans on Nonaccrual with no related allowance (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	$ 12,975	$ 12,861
Nonaccrual with no related ACL	7,246	7,507
90 days or more past due and accruing	20,845	19,702
Consumer loans [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	6,742	6,524
Nonaccrual with no related ACL	1,481	1,661
90 days or more past due and accruing	20,845	19,702
Consumer loans [Member] \| Single family [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	5,489	5,364
Nonaccrual with no related ACL	1,461	1,652
90 days or more past due and accruing	20,845	19,702
Consumer loans [Member] \| Home equity and other [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	1,253	1,160
Nonaccrual with no related ACL	20	9
90 days or more past due and accruing	0	0
Commercial loans [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	6,233	6,337
Nonaccrual with no related ACL	5,765	5,846
90 days or more past due and accruing	0	0
Commercial loans [Member] \| Owner occupied commercial real estate [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	3,050	2,891
Nonaccrual with no related ACL	3,049	2,892
90 days or more past due and accruing	0	0
Commercial loans [Member] \| Commercial business [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	3,183	3,446
Nonaccrual with no related ACL	2,716	2,954
90 days or more past due and accruing	$ 0	$ 0

Amount of financing receivable on nonaccrual status with no allowance for credit loss.

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- Definition

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+ References

No definition available.

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- Definition

Amount of financing receivable 90 days or more past due and still accruing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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- Definition

Amount of financing receivable on nonaccrual status.

+ References

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-Publisher FASB
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