Revenue Recognition - Schedule of Capitalized Contract Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Acquisition Costs
Capitalized Contract Cost [Roll Forward]
Beginning of period balance	$ 160	$ 210	$ 196	$ 203
Costs incurred	26	34	81	106
Amortization	(26)	(30)	(81)	(95)
Change in contract costs held for sale	0	0	(36)	0
End of period balance	160	214	160	214
Acquisition Costs \| Held for sale \| Mass Markets Fiber-to-the Home Business
Capitalized Contract Cost [Roll Forward]
Beginning of period balance			24
Fulfillment Costs
Capitalized Contract Cost [Roll Forward]
Beginning of period balance	290	241	264	222
Costs incurred	57	57	168	166
Amortization	(44)	(41)	(129)	(117)
Change in contract costs held for sale	0	(3)	0	(17)
End of period balance	$ 303	254	303	254
Fulfillment Costs \| Held for sale \| Mass Markets Fiber-to-the Home Business
Capitalized Contract Cost [Roll Forward]
Beginning of period balance		14	$ 21
End of period balance		$ 17		$ 17