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Business Combination & Asset Purchase - Summary of Carrying Amount of Loans (Detail) - USD ($) $ in Thousands | Dec. 31, 2021 | Oct. 01, 2021 | Apr. 30, 2021 | Dec. 31, 2019 | Jan. 01, 2019
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Perpetual Federal Savings Bank [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | $ 510 | $ 728 |  |  |
Perpetual Federal Savings Bank [Member] | Consumer Real Estate [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | 581 | 608 |  |  |
Perpetual Federal Savings Bank [Member] | Agricultural Real Estate [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | 114 | 118 |  |  |
Perpetual Federal Savings Bank [Member] | Commercial Real Estate [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | 5 | 234 |  |  |
Perpetual Federal Savings Bank [Member] | Consumer [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment |  | $ 5 |  |  |
Ossian Financial Services, Inc. [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | 208 |  | $ 1,309 |  |
Ossian Financial Services, Inc. [Member] | Consumer Real Estate [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | 22 |  | 24 |  |
Ossian Financial Services, Inc. [Member] | Agricultural Real Estate [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment |  |  | 981 |  |
Ossian Financial Services, Inc. [Member] | Commercial Real Estate [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | 222 |  | 315 |  |
Ossian Financial Services, Inc. [Member] | Commercial and Industrial [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment | $ 285 |  | $ 314 |  |
Limberlost Bancshares, Inc. [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment |  |  |  | $ 44 | $ 2,278
Limberlost Bancshares, Inc. [Member] | Consumer Real Estate [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment |  |  |  |  | 231
Limberlost Bancshares, Inc. [Member] | Consumer [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment |  |  |  |  | 71
Limberlost Bancshares, Inc. [Member] | Commercial [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Carrying amount, net of fair value adjustment |  |  |  | $ 106 | $ 4,094

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- Definition The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and other-than-temporary impairments), for loans accounted for as debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123409700&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 + Details
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