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Significant Accounting Policies (Long-Lived Assets) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Long-lived asset impairment charge | $ 65,900 | $ 65,887 | $ 3,939
MLMC |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Long-lived asset impairment charge | $ 65,900 |  |

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