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Derivative Instruments and Hedging Activities - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Derivative [Line Items] |  |  |  |  |
Net unrealized gains (losses) arising during the period | $ 27,838,000 | $ (18,274,000) | $ 49,659,000 | $ (75,330,000) |
Pre-tax income (loss) | (4,700,000) | (5,300,000) | (9,200,000) | (10,900,000) |
Cash flow hedge loss to be reclassified |  |  | 25,000,000 |  |
Cash flow hedge termination loss |  |  | 11,000,000 |  |
Reclaim cash collateral | 44,100,000 |  | 44,100,000 |  | $ 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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