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Loans - Activity in the allowance for credit losses by portfolio segment (Details) - USD ($) | 12 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | $ 1,797,116 | $ 2,159,000
Recoveries | 5,000 | 3,000
Provision for (Recovery of) Credit Losses-Loans | (94,000) | (190,000)
Ending Balance | 1,708,269 | 1,797,116
Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | (175,000)
Consumer |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 5,000 | 2,000
Recoveries | 5,000 | 3,000
Provision for (Recovery of) Credit Losses-Loans | (1,000) | (11,000)
Ending Balance | 9,000 | 5,000
Consumer | Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | 11,000
Commercial real estate | Commercial real estate |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 259,000 | 1,196,000
Provision for (Recovery of) Credit Losses-Loans | 131,000 | (119,000)
Ending Balance | 390,000 | 259,000
Commercial real estate | Commercial real estate | Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | (818,000)
Commercial | Commercial and industrial |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 16,000 | 18,000
Provision for (Recovery of) Credit Losses-Loans | (5,000) | (7,000)
Ending Balance | 11,000 | 16,000
Commercial | Commercial and industrial | Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | 5,000
Commercial | Construction |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 28,000 | 6,000
Provision for (Recovery of) Credit Losses-Loans | (24,000) | 20,000
Ending Balance | 4,000 | 28,000
Commercial | Construction | Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | 2,000
Residential | One-to-four-family residential |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 1,314,000 | 207,000
Provision for (Recovery of) Credit Losses-Loans | (191,000) | (30,000)
Ending Balance | 1,123,000 | 1,314,000
Residential | One-to-four-family residential | Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | 1,137,000
Residential | Multi-family real estate |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance | 175,000 | 365,000
Provision for (Recovery of) Credit Losses-Loans | (4,000) | (43,000)
Ending Balance | $ 171,000 | 175,000
Residential | Multi-family real estate | Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | (147,000)
Unallocated |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | 365,000
Unallocated | Cumulative effect of accounting change |  |
Activity in the allowance for credit losses - loans by loan class |  |
Beginning Balance |  | $ (365,000)

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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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- 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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