Restructuring Costs - Schedule of Restructuring Plan Expenses Incurred (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Expenses Incurred	$ 337	$ 1,196	$ 215
Incurred to Date	2,808
Contract termination costs
Restructuring Cost and Reserve [Line Items]
Expenses Incurred	45	231	14
Incurred to Date	468
Severance costs
Restructuring Cost and Reserve [Line Items]
Expenses Incurred	3	169	17
Incurred to Date	574
Network decommissioning
Restructuring Cost and Reserve [Line Items]
Expenses Incurred	289	$ 796	$ 184
Incurred to Date	$ 1,766