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Business Combination and Asset Purchase - Additional Information (Detail) |  |  |  |  |  | 3 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 01, 2022 USD ($) Office $ / shares shares | Oct. 01, 2021 USD ($) Office $ / shares shares | Apr. 30, 2021 USD ($) Office $ / shares shares | Nov. 16, 2020 USD ($) shares | Jan. 01, 2019 USD ($) shares $ / shares | Mar. 31, 2025 USD ($) shares | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) shares | Nov. 30, 2020 USD ($) Client
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Common stock, shares outstanding | shares |  |  |  |  |  | 13,718,336 |  | 13,699,536 |
Goodwill |  |  |  |  |  | $ 86,358,000 |  | $ 86,358,000 |
Amortization expense |  |  |  |  |  | 414,000 | $ 414,000 |  |
Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Amortization expense |  |  |  |  |  | 414,000 | 414,000 |  |
Amortization expense for 2023 |  |  |  |  |  | 1,656,000 |  |  |
Customer Lists [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Amortization expense |  |  |  |  |  | 31,000 | $ 31,000 |  |
Amortization expense for 2023 |  |  |  |  |  | 123,000 |  |  |
Peoples Federal Savings and Loan [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Number of full-service offices | Office | 3 |  |  |  |  |  |  |  |
Common stock issued in exchange of each outstanding share | 0.6597 |  |  |  |  |  |  |  |
Cash payment for exchange of each share | $ / shares | $ 24.00 |  |  |  |  |  |  |  |
Minimum number of shares to be exchanged under merger agreement | shares | 758,566 |  |  |  |  |  |  |  |
Common stock, shares outstanding | shares | 1,167,025 |  |  |  |  |  |  |  |
Share price | $ / shares | $ 26.87 |  |  |  |  |  |  |  |
Total consideration for acquisition | $ 23,200,000 |  |  |  |  |  |  |  |
Cash paid for the capital stock | 9,800,000 |  |  |  |  |  |  |  |
Stock issued for acquisition | 13,400,000 |  |  |  |  |  |  |  |
Goodwill | 5,900,000 |  |  |  |  |  |  |  |
Peoples Federal Savings and Loan [Member] | Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit intangible asset with acquired purchase | $ 6,000,000 |  |  |  |  |  |  |  |
Remaining economic useful life | 7 years |  |  |  |  |  |  |  |
Recognition of core deposit tangible asset with acquired purchase |  |  |  |  |  | 6,000,000 |  |  |
Amortization expense for 2023 |  |  |  |  |  | 861,000 |  |  |
Perpetual Federal Savings Bank [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Number of full-service offices | Office |  | 1 |  |  |  |  |  |  |
Common stock issued in exchange of each outstanding share |  | 1.7766 |  |  |  |  |  |  |
Cash payment for exchange of each share | $ / shares |  | $ 41.20 |  |  |  |  |  |  |
Business acquisition share owned subject to adjustment | shares |  | 1,833,999 |  |  |  |  |  |  |
Common stock, shares outstanding | shares |  | 2,470,032 |  |  |  |  |  |  |
Share price | $ / shares |  | $ 22.4 |  |  |  |  |  |  |
Total consideration for acquisition |  | $ 100,300,000 |  |  |  |  |  |  |
Cash paid for the capital stock |  | 59,200,000 |  |  |  |  |  |  |
Stock issued for acquisition |  | 41,100,000 |  |  |  |  |  |  |
Goodwill |  | 25,200,000 |  |  |  |  |  |  |
Perpetual Federal Savings Bank [Member] | Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit intangible asset with acquired purchase |  | $ 668,000 |  |  |  |  |  |  |
Remaining economic useful life |  | 7 years |  |  |  |  |  |  |
Amortization expense for 2023 |  |  |  |  |  | 95,000 |  |  |
Ossian State Bank [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Number of full-service offices | Office |  |  | 2 |  |  |  |  |  |
Ossian State Bank [Member] | Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit tangible asset with acquired purchase |  |  |  |  |  | 980,200 |  |  |
Ossian Financial Services, Inc. [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Cash payment for exchange of each share | $ / shares |  |  | $ 67.71 |  |  |  |  |  |
Common stock, shares outstanding | shares |  |  | 295,388 |  |  |  |  |  |
Total consideration for acquisition |  |  | $ 20,000,000.0 |  |  |  |  |  |
Goodwill |  |  | $ 7,900,000 |  |  |  |  |  |
Goodwill deductible for tax purpose, period |  |  | 15 years |  |  |  |  |  |
Ossian Financial Services, Inc. [Member] | Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit intangible asset with acquired purchase |  |  | $ 980,200 |  |  |  |  |  |
Remaining economic useful life |  |  | 7 years |  |  |  |  |  |
Amortization expense for 2023 |  |  |  |  |  | 140,000 |  |  |
Bank of Geneva [Member] | Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit intangible asset with acquired purchase |  |  |  |  |  | $ 3,900,000 |  |  |
Remaining economic useful life |  |  |  |  |  | 7 years |  |  |
Limberlost Bancshares, Inc. [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Common stock issued in exchange of each outstanding share | shares |  |  |  |  | 1,830 |  |  |  |
Cash payment for exchange of each share | $ / shares |  |  |  |  | $ 8,465 |  |  |  |
Common stock, shares outstanding | shares |  |  |  |  | 1,000 |  |  |  |
Share price | $ / shares |  |  |  |  | $ 38.49 |  |  |  |
Total consideration for acquisition |  |  |  |  | $ 78,900,000 |  |  |  |
Cash paid for the capital stock |  |  |  |  | 8,500,000 |  |  |  |
Stock issued for acquisition |  |  |  |  | 70,400,000 |  |  |  |
Goodwill |  |  |  |  | 43,300,000 |  |  |  |
Limberlost Bancshares, Inc. [Member] | Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit intangible asset with acquired purchase |  |  |  |  | $ 3,900,000 |  |  |  |
Remaining economic useful life |  |  |  |  | 7 years |  |  |  |
Perpetual Federal Savings Bank [Member] | Core Deposits [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit tangible asset with acquired purchase |  |  |  |  |  | $ 668,000 |  |  |
Adams County Financial Resources [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Total consideration for acquisition |  |  |  | $ 825,000 |  |  |  |  |
Common stock issued in exchange of each outstanding share | shares |  |  |  | 40,049 |  |  |  |  |
Assets under management amount |  |  |  |  |  |  |  |  | $ 83,000,000
Number of clients assets under management | Client |  |  |  |  |  |  |  |  | 450
Adams County Financial Resources [Member] | Customer Lists [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Recognition of core deposit intangible asset with acquired purchase |  |  |  | $ 800,000 |  |  |  |  |
Remaining economic useful life |  |  |  | 6 years 6 months |  |  |  |  |
Amortization expense for 2023 |  |  |  |  |  | $ 123,000 |  |  |

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