LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES - LOANS - Financing Receivables, Related Allowance Recorded and No Related Allowance Recorded (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, with no related allowance recorded	$ 756
Unpaid Principal Balance, with an allowance recorded	5,134
Impaired Financing Receivable, Unpaid Principal Balance, Total	5,890
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment, with no related allowance recorded	707
Recorded Investment, with an allowance recorded	5,122
Recorded Investment	5,829
Impaired Financing Receivable Related Allowance Abstract
Related Allowance, with no related allowance recorded	0
Related Allowance, with an allowance recorded	1,163
Related Allowance	1,163
REAL ESTATE LOANS \| Home equity.
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, with no related allowance recorded	259
Unpaid Principal Balance, with an allowance recorded	92
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment, with no related allowance recorded	227
Recorded Investment, with an allowance recorded	74
Impaired Financing Receivable Related Allowance Abstract
Related Allowance, with no related allowance recorded	0
Related Allowance, with an allowance recorded	23
REAL ESTATE LOANS \| One-to-four-family
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, with no related allowance recorded	497
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment, with no related allowance recorded	480
Impaired Financing Receivable Related Allowance Abstract
Related Allowance, with no related allowance recorded	0
CONSUMER LOANS \| Indirect home improvement
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, with an allowance recorded	551
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment, with an allowance recorded	554
Impaired Financing Receivable Related Allowance Abstract
Related Allowance, with an allowance recorded	193
CONSUMER LOANS \| Marine
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, with an allowance recorded	56
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment, with an allowance recorded	57
Impaired Financing Receivable Related Allowance Abstract
Related Allowance, with an allowance recorded	20
CONSUMER LOANS \| Other consumer loans
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, with an allowance recorded	18
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment, with an allowance recorded	18
Impaired Financing Receivable Related Allowance Abstract
Related Allowance, with an allowance recorded	6
COMMERCIAL BUSINESS LOANS \| Commercial and industrial
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, with an allowance recorded	4,417
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment, with an allowance recorded	4,419
Impaired Financing Receivable Related Allowance Abstract
Related Allowance, with an allowance recorded	$ 921

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
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Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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