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Commitments and Credit Risk - Additional Information (Detail) - USD ($) | 12 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024
Commitments And Contingencies Disclosure [Line Items] |  |
Outstanding commitments to originate loans amount | $ 7,631,000 | $ 8,317,000
Loan amount commitments at fixed rates of interest | $ 5,296,000 | $ 2,028,000
Weighted average interest rates for fixed rate loan commitments | 7.18% | 7.43%
Off-Balance-Sheet, Credit loss, Liability | $ 75,000 | $ 98,000
Off-Balance-Sheet, Credit Loss,Credit Loss Expense | 23,000 | 118,000
Commercial [Member] |  |
Commitments And Contingencies Disclosure [Line Items] |  |
Lines of credit to borrowers | 55,815,000 | 58,696,000
Open End Consumer Lines [Member] |  |
Commitments And Contingencies Disclosure [Line Items] |  |
Lines of credit to borrowers | $ 13,843,000 | $ 12,545,000

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- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482454/460-10-45-1 + Details
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