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Business Combination and Asset Purchase - Summary of Changes in Accretable Yield or Income Expected to be Collected (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Peoples Federal Savings and Loan [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | $ 335 | $ 566
Additions | 0 |
Accretion | (58) | (58)
Reclassification from nonaccretable difference | 0 |
Disposals | 0 |
Ending Balance | 277 | 508
Perpetual Federal Savings Bank [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | 1,453 | 2,795
Additions | 0 |
Accretion | (336) | (335)
Reclassification from nonaccretable difference | 0 |
Disposals | 0 |
Ending Balance | 1,117 | 2,460
Ossian Financial Services, Inc. [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | 107 | 294
Additions | 0 |
Accretion | (40) | (44)
Reclassification from nonaccretable difference | 0 |
Disposals | 0 |
Ending Balance | 67 | 250
Limberlost Bancshares, Inc. [Member] |  |
Business Acquisition [Line Items] |  |
Beginning Balance | 0 | 363
Additions | 0 |
Accretion | 0 | (109)
Reclassification from nonaccretable difference | 0 |
Disposals | 0 |
Ending Balance | $ 0 | $ 254

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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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