Derivative Instruments and Hedging Activities - Designated as fair value hedges (Details) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Cash Flow Hedging Derivatives | ||
| Termination of fair value hedges on treasury and municipal securities | $ 10,400 | |
| Interest Rate Swaps | ||
| Cash Flow Hedging Derivatives | ||
| Proceeds from termination of interest rate swaps | 195,900 | |
| Termination of fair value hedges on treasury and municipal securities | 10,400 | |
| Fair Value Hedging | Designated as Hedging Instrument | Interest Rate Swaps | ||
| Cash Flow Hedging Derivatives | ||
| Notional Amount | $ 116,491 | $ 242,314 |
| Weighted Average Pay Rate | 4.38% | 3.55% |
| Weighted Average Receive Rate | 3.76% | 4.20% |
| Weighted Average Maturity (Years) | 15 years 6 months 18 days | 14 years 6 months 14 days |
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- Definition Weighted average pay rate in effect as of the balance sheet date related to the interest rate derivative. No definition available.
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- Definition Weighted average receive rate in effect as of the balance sheet date related to the interest rate derivative. No definition available.
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- Definition Amount of unrealized and realized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity), investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Average period remaining until maturity of derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash inflow from the sale of investments classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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