Other Financial Information - Schedule of Other Current Assets, Net (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Prepaid Expenses and Other Current Assets [Abstract]
Prepaid expenses	$ 437	$ 404
Income tax receivable	13	468
Materials, supplies and inventory	122	165
Contract assets	16	18
Other	37	18
Total other current assets, net	856	1,307
Held for sale \| Mass Markets Fiber-to-the Home Business
Other Current Assets [Line Items]
Other current assets, net		30
Acquisition Costs
Prepaid Expenses and Other Current Assets [Abstract]
Contract costs	83	98
Fulfillment Costs
Prepaid Expenses and Other Current Assets [Abstract]
Contract costs	$ 148	$ 136

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