Wireless Licenses, Goodwill and Other Intangible Assets - Amortization Expense for Other Intangible Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense for other intangible assets	$ 2,781	$ 2,687	$ 2,507