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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
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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

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- 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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