Acquisitions - Schedule of Preliminary Purchase Price Allocation (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Apr. 01, 2022	Dec. 31, 2021
Allocation of purchase price consideration
Goodwill	$ 5,504	$ 5,737	$ 5,654		$ 5,372
Entel Chile
Allocation of purchase price consideration
Cash and cash equivalents		0
Accounts receivable		0
Other current assets		12
Property, plant and equipment		81
Intangible assets		153
Goodwill		381
Deferred tax and other assets		12
Total assets acquired		639
Accounts payable and accrued liabilities		0
Other current liabilities		0
Mortgage and loans payable		0
Deferred tax and other liabilities		(1)
Net assets acquired		638
Entel Peru
Allocation of purchase price consideration
Cash and cash equivalents		0
Accounts receivable		0
Other current assets		0
Property, plant and equipment		13
Intangible assets		10
Goodwill		46
Deferred tax and other assets		11
Total assets acquired		80
Accounts payable and accrued liabilities		0
Other current liabilities		0
Mortgage and loans payable		0
Deferred tax and other liabilities		0
Net assets acquired		80
MainOne
Allocation of purchase price consideration
Cash and cash equivalents		33
Accounts receivable		9
Other current assets		22
Property, plant and equipment		239
Intangible assets		55
Goodwill		111
Deferred tax and other assets		6
Total assets acquired		475
Accounts payable and accrued liabilities		(19)
Other current liabilities		(13)
Mortgage and loans payable		(26)
Deferred tax and other liabilities		(139)
Net assets acquired		$ 278
Deferred revenue, current				$ 10
Deferred revenue, noncurrent				$ 95