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Off-Balance Sheet Credit Exposures - Schedule of Notional Amounts of Financial Instruments with Off-Balance Sheet Credit Risk (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Unadvanced portions of loans [Member]
Fair Value, off-Balance-Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet credit risk	$ 47,392	$ 44,929
Commitments to originate loans [Member]
Fair Value, off-Balance-Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet credit risk	$ 20,026	16,134
Standby Letters of Credit [Member]
Fair Value, off-Balance-Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet credit risk		$ 302

X

- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

+ Details

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X

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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