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Derivative Financial Instruments - Narrative (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2025 | Dec. 31, 2024
Derivative Instruments, Gain (Loss) [Line Items] |  |
Cash collateral pledged | $ 12,053 | $ 80
Current net credit exposure | 76,300 |
Non-performance risk in fair value measurement | 4,200 | $ 7,600
Cash and Due from Banks |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Cash collateral pledged | 13,800 |
CME Swaps Markets |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Initial margin posted at clearing house | 3,500 |
Valuation, Cost Approach |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Cash collateral pledged | 84,500 |
Valuation, Market Approach |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Current net credit exposure | $ 126,900 |
Cash Flow Hedging |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Maximum time for forecasted transactions | 2 years 1 month 6 days |

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