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Disclosures About Fair Value of Assets - Fair Value Measurements of Assets Recognized on Recurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Jun. 30, 2025
--- | --- | ---
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | $ 189,824 | $ 187,753
Mortgage servicing rights | 1,430 | 1,429
U.S. Government and federal agency and Government sponsored enterprises (GSE's) [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | 916 | 1,812
Mortgage-backed: GSE residential [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | 174,345 | 171,079
Small Business Administration [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | 12,815 | 13,114
State and political subdivisions [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | 1,748 | 1,748
Significant Other Observable Inputs (Level 2) [Member] | U.S. Government and federal agency and Government sponsored enterprises (GSE's) [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | 916 | 1,812
Significant Other Observable Inputs (Level 2) [Member] | Mortgage-backed: GSE residential [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | 174,345 | 171,079
Significant Other Observable Inputs (Level 2) [Member] | Small Business Administration [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | 12,815 | 13,114
Significant Unobservable Inputs (Level 3) [Member] |  |
Available-for-sale securities: |  |
Mortgage servicing rights | 1,430 | 1,429
Significant Unobservable Inputs (Level 3) [Member] | State and political subdivisions [Member] |  |
Available-for-sale securities: |  |
Available-for-sale securities, Fair Value | $ 1,748 | $ 1,748

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