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Significant Accounting Policies - Derivative Accounting (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional derivative contracts | $ 920,617 | $ 1,906,092
CME |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional derivative contracts | $ 850,000 |
Percent of total notional derivative contracts | 92.30% |
Amount of variation margin included as settlement | $ (22,000) |
LCH |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional derivative contracts | $ 71,000 |
Percent of total notional derivative contracts | 7.70% |
Amount of variation margin included as settlement | $ (1,000) |

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