Business Combination and Asset Purchase - Summary of Changes in Accretable Yield or Income Expected to be Collected (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Peoples Federal Savings and Loan [Member]
Business Acquisition [Line Items]
Beginning Balance	$ 798
Additions	1
Accretion	(58)
Ending Balance	741		$ 798
Perpetual Federal Savings Bank [Member]
Business Acquisition [Line Items]
Beginning Balance	4,236	$ 5,262	5,262
Additions	14	64
Accretion	(344)	(322)
Ending Balance	3,906	5,004	4,236
Ossian Financial Services, Inc. [Member]
Business Acquisition [Line Items]
Beginning Balance	470	645	645
Accretion	(44)	(44)
Ending Balance	426	601	470
Limberlost Bancshares, Inc. [Member]
Business Acquisition [Line Items]
Beginning Balance	785	1,198	1,198
Additions	3	5
Accretion	(107)	(106)
Ending Balance	$ 681	$ 1,097	$ 785

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan 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)(2)
-URI https://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

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- Definition

Current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan 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 50
-Paragraph 2
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

Reference 2: 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

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- Definition

Increases in the aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan due to the acquisition of similar loans accounted for as debt securities during the period. This relates to 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

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