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Loans - Activity in the allowance for credit losses by portfolio segment (Details) - USD ($) | 3 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | $ 1,708,269 | $ 1,797,000
Recoveries | 1,000 |
Provision for (Recovery of) Credit Losses-Loans | (40,000) | (155,000)
Ending Balance | 1,668,782 | 1,642,000
Consumer |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 9,000 |
Recoveries | 1,000 |
Provision for (Recovery of) Credit Losses-Loans | 7,000 |
Ending Balance | 17,000 |
Commercial real estate | Commercial real estate |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 390,000 | 259,000
Provision for (Recovery of) Credit Losses-Loans | 28,000 | (15,000)
Ending Balance | 418,000 | 244,000
Commercial | Commercial and industrial |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 11,000 | 16,000
Provision for (Recovery of) Credit Losses-Loans | 3,000 | (1,000)
Ending Balance | 14,000 | 15,000
Commercial | Construction |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 4,000 | 28,000
Provision for (Recovery of) Credit Losses-Loans | 1,000 | (28,000)
Ending Balance | 5,000 |
Residential | One-to-four-family residential |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 1,123,000 | 1,314,000
Provision for (Recovery of) Credit Losses-Loans | (144,000) | (104,000)
Ending Balance | 979,000 | 1,210,000
Residential | Multi-family real estate |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 171,000 | 175,000
Provision for (Recovery of) Credit Losses-Loans | 65,000 | (7,000)
Ending Balance | $ 236,000 | 168,000
Consumer Loans |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | 5,000
Ending Balance |  | $ 5,000

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References 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 + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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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 + Details
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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. + Details
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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 + Details
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