Other Financial Information - Other Current Liabilities (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Current affiliate obligation	$ 48	$ 48
Current operating lease liability	13	15
Other	44	54
Total Other current liabilities	105	117
Capital expenditures	9	$ 57
Held-for-sale \| Lumen Mass Markets fiber-to-the-home business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other current liabilities	2
Accounts payable	$ 17

Other Liabilities, Miscellaneous, Current

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Amount classified as accounts payable attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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