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Fair Values of Assets and Liabilities - Summary of Significant Unobservable Inputs used in Level 3 Assets Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Inputs, Level 3 [Member] - Fair Value, Measurements, Recurring [Member] $ in Thousands | 6 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2021 USD ($)
Mortgage servicing rights [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights | [1] | $ 350 | $ 357 | $ 364 | $ 322
Prepayment Rate [Member] | Mortgage servicing rights [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Servicing Asset, Valuation Technique [Extensible List] |  | us-gaap:ValuationTechniqueDiscountedCashFlowMember | us-gaap:ValuationTechniqueDiscountedCashFlowMember |  |
Mortgage Servicing Rights |  | $ 350 | $ 357 |  |
Prepayment Rate [Member] | Minimum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.057 | 0.0648 |  |
Prepayment Rate [Member] | Maximum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.2069 | 0.2349 |  |
Prepayment Rate [Member] | Weighted Average [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs | [2] | 0.0778 | 0.0778 |  |
Fair value valuation techniques |  | Prepayment Rate | Prepayment Rate |  |
Discount Rate [Member] | Minimum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.095 | 0.095 |  |
Discount Rate [Member] | Maximum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.095 | 0.095 |  |
Discount Rate [Member] | Weighted Average [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs | [2] | 0.0900 | 0.0950 |  |
Fair value valuation techniques |  | Discount Rate | Discount Rate |  |
Delinquency Rate [Member] | Minimum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.0182 | 0.0213 |  |
Delinquency Rate [Member] | Maximum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.0247 | 0.0279 |  |
Delinquency Rate [Member] | Weighted Average [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs | [2] | 0.0236 | 0.0224 |  |
Fair value valuation techniques |  | Delinquency Rate | Delinquency Rate |  |
Default Rate [Member] | Minimum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.0014 | 0.0014 |  |
Default Rate [Member] | Maximum [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs |  | 0.002 | 0.002 |  |
Default Rate [Member] | Weighted Average [Member] |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |
Mortgage Servicing Rights, Measuring Inputs | [2] | 0.0015 | 0.0015 |  |
Fair value valuation techniques |  | Default Rate | Default Rate |  |
[1] | Realized and unrealized gains and losses related to mortgage servicing rights are reported as a component of loan servicing fee income in the Company’s consolidated statements of (loss) income.
[2] | Unobservable inputs for mortgage servicing rights were weighted by loan amount.

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