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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
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

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+ References

No definition available.

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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

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