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Derivative Instruments and Hedging Activities (Narrative) (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Derivative [Line Items] |  |  |
Net unrealized gains (losses) arising during the period | $ 10,000,000 | $ (135,978,000) |
Income (loss) recognized | 5,400,000 | 2,200,000 |
Cash flow hedge gain (loss) to be reclassified | (149,000,000) |  |
Cash flow hedge termination gain | 24,000,000 |  |
Right to reclaim cash collateral | 86,500,000 |  | $ 66,800,000
Obligation to return cash collateral | 7,700,000 |  | $ 7,700,000
Cash Flow Hedges |  |  |
Derivative [Line Items] |  |  |
Net unrealized gains (losses) arising during the period | $ 0 | $ 0 |

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