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Fair Value of Financial Instruments - Additional Information (Detail) | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2022 Security | Sep. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Sep. 30, 2022 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Security transfer from Level 3 to Level 2 | Security | 1 |  |  |
Collateral dependent loans categorized as Level 3 |  |  | $ 8,857,000 | $ 10,753,000
Impairment |  | $ 3,000 | 0 |
Level 3 [Member] | Collateral Dependent [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Collateral dependent loans categorized as Level 3 |  | $ 312,000 | $ 2,700,000 |

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