Business Combination & Asset Purchase - Schedule of Future Amortization of Core Deposit Intangible Assets (Detail) $ in Thousands	Dec. 31, 2024 USD ($)
Core Deposits [Member]
Business Acquisition [Line Items]
2025	$ 1,656
2026	1,096
2027	1,096
2028	981
2029	646
Total	5,475
Core Deposits [Member] \| Geneva [Member]
Business Acquisition [Line Items]
2025	560
Total	560
Core Deposits [Member] \| Ossian [Member]
Business Acquisition [Line Items]
2025	140
2026	140
2027	140
2028	47
Total	467
Core Deposits [Member] \| Perpetual Federal Savings Bank [Member]
Business Acquisition [Line Items]
2025	95
2026	95
2027	95
2028	73
Total	358
Core Deposits [Member] \| Peoples Federal Savings and Loan [Member]
Business Acquisition [Line Items]
2025	861
2026	861
2027	861
2028	861
2029	646
Total	4,090
Customer Lists [Member] \| Adams County Financial Resources [Member]
Business Acquisition [Line Items]
2025	123
2026	123
2027	48
Total	$ 294

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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