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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 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 |  |  | $ 2,779,000
Unrecognized deferred taxes | $ 1,040,000 |  |
Peoples Federal Savings and Loan [Member] |  |  |
Income Taxes [Line Items] |  |  |
Operating loss carryforwards | 2,000 | $ 2,600 |
Operating loss carryforward at acquisition | $ 2,789,124 |  |
Deferred taxes business combination allocated to additional paid in capital |  | $ 2,174,000 |

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