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Business Combination and Asset Purchase - Summary of Carrying Amount of Loans (Parenthetical) (Detail) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021 | Oct. 01, 2021 | Apr. 30, 2021
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Perpetual Federal Savings Bank [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Fair value adjustment | $ 141 | $ 190 | $ 237 |
Ossian Financial Services, Inc. [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Fair value adjustment | $ 10 | $ 321 |  | $ 325

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- Details
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