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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Perpetual Federal Savings Bank [Member]
Income Taxes [Line Items]
Deferred taxes business combination allocated to additional paid in capital				$ 2.8
Unrecognized deferred taxes	$ 1.0
Peoples Federal Savings and Loan [Member]
Income Taxes [Line Items]
Operating loss carryforwards	1.4	$ 2.0
Operating loss carryforward at acquisition	$ 2.8
Deferred taxes business combination allocated to additional paid in capital			$ 2.2

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Deferred taxes business combination allocated to additional paid in capital.

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Income Taxes [Line Items]

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- Definition

Operating loss carryforward at acquisition.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

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- Definition

Amount of unrecognized tax benefits.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 217
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-217

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Section 50
-Paragraph 15A
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-Publisher FASB
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