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Business Combination & Asset Purchase - Summary of Changes in Accretable Yield or Income Expected to be Collected (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Peoples Federal Savings and Loan [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | $ 566 | $ 798
Additions |  | 6
Accretion | (231) | (232)
Disposals |  | (6)
Ending Balance | 335 | 566
Perpetual Federal Savings Bank [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | 2,795 | 4,236
Additions |  | 39
Accretion | (1,342) | (1,480)
Ending Balance | 1,453 | 2,795
Ossian Financial Services, Inc. [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | 294 | 470
Accretion | (175) | (176)
Disposals | (12) |
Ending Balance | 107 | 294
Limberlost Bancshares, Inc. [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | 363 | 785
Additions | 1 | 11
Accretion | $ (364) | (433)
Ending Balance |  | $ 363

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479907/805-20-50-5 + Details
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