Loans - Activity in the allowance for credit losses by portfolio segment (Details) - USD ($)	3 Months Ended	6 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024
Activity in the allowance for credit losses - loans by loan class
Beginning Balance	$ 1,669,000	$ 1,642,000	$ 1,708,269	$ 1,797,000
Recoveries	1,000	1,000	2,000	1,000
Provision for (Recovery of) Credit Losses-Loans	33,000	8,000	(7,000)	(147,000)
Ending Balance	1,702,526	1,651,000	1,702,526	1,651,000
Consumer
Activity in the allowance for credit losses - loans by loan class
Beginning Balance	17,000	5,000	9,000	5,000
Recoveries	1,000	1,000	2,000	1,000
Provision for (Recovery of) Credit Losses-Loans		3,000	7,000	3,000
Ending Balance	18,000	9,000	18,000	9,000
Commercial real estate \| Commercial real estate
Activity in the allowance for credit losses - loans by loan class
Beginning Balance	418,000	244,000	390,000	259,000
Provision for (Recovery of) Credit Losses-Loans	(51,000)	18,000	(23,000)	3,000
Ending Balance	367,000	262,000	367,000	262,000
Commercial \| Commercial and industrial
Activity in the allowance for credit losses - loans by loan class
Beginning Balance	14,000	15,000	11,000	16,000
Provision for (Recovery of) Credit Losses-Loans	(4,000)	(1,000)	(1,000)	(2,000)
Ending Balance	10,000	14,000	10,000	14,000
Commercial \| Construction
Activity in the allowance for credit losses - loans by loan class
Beginning Balance	5,000		4,000	28,000
Provision for (Recovery of) Credit Losses-Loans	(4,000)		(3,000)	(28,000)
Ending Balance	1,000		1,000
Residential \| One-to-four-family residential
Activity in the allowance for credit losses - loans by loan class
Beginning Balance	979,000	1,210,000	1,123,000	1,314,000
Provision for (Recovery of) Credit Losses-Loans	121,000	(1,000)	(23,000)	(105,000)
Ending Balance	1,100,000	1,209,000	1,100,000	1,209,000
Residential \| Multi-family real estate
Activity in the allowance for credit losses - loans by loan class
Beginning Balance	236,000	168,000	171,000	175,000
Provision for (Recovery of) Credit Losses-Loans	(29,000)	(11,000)	36,000	(18,000)
Ending Balance	$ 207,000	$ 157,000	$ 207,000	$ 157,000

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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