Wireless Licenses, Goodwill and Other Intangible Assets - Additional Information (Detail) - Wireless Licenses - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Indefinite-lived Intangible Assets [Line Items]
Wireless licenses under development	$ 8,600	$ 11,800
Interest costs capitalized	$ 234	$ 338
Average remaining renewal period of wireless license portfolio (in years)	10 years