DEPOSITS - Interest expense on deposits (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
DEPOSITS.
NOW accounts	$ 6	$ 6	$ 12	$ 12
Regular savings and demand clubs	34	3	51	7
Money markets	443	376	839	702
Certificates of deposit and retirement accounts	512	637	1,020	1,230
Total	$ 995	$ 1,022	$ 1,922	$ 1,951

Amount of interest expense on domestic certificates of deposit and retirement accounts.

No definition available.

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- Definition

Amount of interest expense on domestic regular savings and demand clubs.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Aggregate amount of interest expense on all deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-21

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

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- Definition

Amount of interest expense on domestic money market demand account deposit liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

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Period Type:	duration

- Definition

Amount of interest expense on domestic notice of withdrawal demand deposit liabilities.

+ References

+ Details

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