Business Combination and Asset Purchase - Summary of Changes in Accretable Yield or Income Expected to be Collected (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Peoples Federal Savings and Loan [Member]
Business Acquisition [Line Items]
Beginning Balance	$ 566	$ 798
Additions		1
Accretion	(58)	(58)
Ending Balance	508	741
Perpetual Federal Savings Bank [Member]
Business Acquisition [Line Items]
Beginning Balance	2,795	4,236
Additions		14
Accretion	(335)	(344)
Ending Balance	2,460	3,906
Ossian Financial Services, Inc. [Member]
Business Acquisition [Line Items]
Beginning Balance	294	470
Accretion	(44)	(44)
Ending Balance	250	426
Limberlost Bancshares, Inc. [Member]
Business Acquisition [Line Items]
Beginning Balance	363	785
Additions		3
Accretion	(109)	(107)
Ending Balance	$ 254	$ 681

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479907/805-20-50-5

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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
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481906/310-30-15-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481696/310-30-50-2

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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.

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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.

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