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Business Combination and Asset Purchase - Summary of Carrying Amount of Loans (Detail) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021 | Oct. 01, 2021 | Apr. 30, 2021
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Perpetual Federal Savings Bank [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Carrying amount, net of fair value adjustment | $ 303 | $ 510 | $ 728 |
Perpetual Federal Savings Bank [Member] | Consumer Real Estate [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Carrying amount, net of fair value adjustment | 336 | 581 | 608 |
Perpetual Federal Savings Bank [Member] | Agricultural Real Estate [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Carrying amount, net of fair value adjustment | 108 | 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] | Commercial and Industrial [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 | 10 | 208 |  | $ 1,309
Ossian Financial Services, Inc. [Member] | Consumer Real Estate [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Carrying amount, net of fair value adjustment | $ 20 | 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

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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 https://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 https://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 + Details
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