Other Financial Information - Current Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Current affiliate obligation	$ 44	$ 44
Current operating lease liability	14	14
Other	80	51
Total Other current liabilities	138	109
Capital expenditures	37	$ 37
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	$ 4

Other Liabilities, Miscellaneous, Current

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Amount classified as other liabilities 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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