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Commitments and Contingent Liabilities - Additional Information (Detail) - USD ($)	Jun. 30, 2025	Dec. 31, 2024
Loss Contingencies [Line Items]
Notional Amount Of Performance Standby Letters Of Credit	$ 1,900,000
Notional Amount Of Commercial Letters Of Credit	0
Notional Amount Of Financial Standby Letters Of Credit	0
Financial instrument of credit risk	300,000	$ 300,000
Off-Balance-Sheet, Credit Loss, Liability	6,700,000	$ 4,100,000
Minimum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	0
Maximum [Member]
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 1,000,000

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Fair value of commitment subject to concentration of credit or market risk or both.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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