| Off-Balance Sheet Commitments - Allowance for Credit Losses Related to Off-Balance Sheet Items (Detail) - USD ($) $ in Thousands | 3 Months Ended | |
|---|---|---|
| Mar. 31, 2025 | Mar. 31, 2024 | |
| Risks and Uncertainties [Abstract] | ||
| Balance at beginning of period | $ 2,074 | $ 2,474 | 
| Credit loss expense (recovery) | 325 | (177) | 
| Balance at end of period | $ 2,399 | $ 2,297 | 
| X | ||||||||||
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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| X | ||||||||||
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- Definition Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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| X | ||||||||||
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- References No definition available. 
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