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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, 2025

USD ($)

Dec. 31, 2024

USD ($)

Jun. 30, 2024

USD ($)

Dec. 31, 2023

USD ($)

Mortgage servicing rights [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights

^[1]

$ 280

$ 305

$ 321

$ 339

Prepayment Rate [Member] | Mortgage servicing rights [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Servicing Asset, Valuation Technique [Extensible List]

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Mortgage Servicing Rights

$ 280

$ 305

Prepayment Rate [Member] | Minimum [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

0.0449

0.0454

Prepayment Rate [Member] | Maximum [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

0.2371

0.1871

Prepayment Rate [Member] | Weighted Average [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

^[2]

0.0838

0.0651

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

0.10

Discount Rate [Member] | Maximum [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

0.095

0.10

Discount Rate [Member] | Weighted Average [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

^[2]

0.095

0.10

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

0.019

0.0217

Delinquency Rate [Member] | Maximum [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

0.0253

0.0264

Delinquency Rate [Member] | Weighted Average [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

^[2]

0.0201

0.0225

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

0.0016

0.0014

Default Rate [Member] | Maximum [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

0.0032

0.0024

Default Rate [Member] | Weighted Average [Member]

Fair Value Measurement Inputs and Valuation Techniques [Line Items]

Mortgage Servicing Rights, Measuring Inputs

^[2]

0.0019

0.0016

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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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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