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Derivative Instruments and Hedging Activities - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Derivative [Line Items] |  |  |  |  |
Net unrealized gains (losses) arising during the period | $ (7,954,000) | $ 52,985,000 | $ 41,705,000 | $ (22,345,000) |
Pre-tax income (loss) | (4,800,000) | (4,900,000) | (14,000,000) | (15,800,000) |
Cash flow hedge loss to be reclassified |  |  | 12,000,000 |  |
Cash flow hedge termination loss |  |  | 7,000,000 |  |
Reclaim cash collateral | 15,500,000 |  | 15,500,000 |  | $ 34,600,000
Obligation to return cash collateral | 4,600,000 |  | 4,600,000 |  | $ 4,600,000
Cash Flow Hedges |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Net unrealized gains (losses) arising during the period | $ 0 | $ 0 | $ 0 | $ 0 |

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