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Employee Benefits - Additional Information (Details) - Combined Pension Plan $ in Millions | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2022 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Jan. 01, 2022 USD ($) Employee | Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Benefit obligation |  | $ 4,816 | $ 5,212 | $ 5,295 |  | $ 9,678
Fair value of plan assets (liabilities) |  | 4,201 | 4,476 | 4,715 |  | $ 8,531
Contributions |  | $ 170 | $ 0 | $ 0 |  |
New Lumen Pension Plan |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Number of active participants (in employees) | Employee |  |  |  |  | 2,500 |
Number of other participants (in employees) | Employee |  |  |  |  | 19,000 |
Benefit obligation |  |  |  |  | $ 2,500 |
Fair value of plan assets (liabilities) |  |  |  |  | $ 2,200 |
Contributions | $ 319 |  |  |  |  |

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