Restructuring Costs - Narrative (Details) $ in Millions	3 Months Ended
Restructuring Costs - Narrative (Details) $ in Millions	Mar. 31, 2026 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring expected period	2 years
UScellular Acquisition Restructuring Initiatives
Restructuring Cost and Reserve [Line Items]
Amortization of the right-of-use assets on lease contracts	$ 280
UScellular Acquisition Restructuring Initiatives \| Network decommissioning
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, accelerated depreciation	229
Network Optimization Restructuring Initiatives
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, accelerated depreciation	60
Network Optimization Restructuring Initiatives \| Network decommissioning
Restructuring Cost and Reserve [Line Items]
Amortization of the right-of-use assets on lease contracts	$ 11

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details