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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
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Perpetual Federal Savings Bank [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Deferred taxes business combination allocated to additional paid in capital |  |  |  | $ 2.8
Unrecognized deferred taxes | $ 1.0 |  |  |
Peoples Federal Savings and Loan [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Operating loss carryforwards | 1.4 | $ 2.0 |  |
Operating loss carryforward at acquisition | $ 2.8 |  |  |
Deferred taxes business combination allocated to additional paid in capital |  |  | $ 2.2 |

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