v3.25.3
Leases - Narrative (Details)
$ in Millions
3 Months Ended 9 Months Ended
Aug. 01, 2025
USD ($)
tower_site
Sep. 30, 2025
USD ($)
Sep. 30, 2024
USD ($)
Sep. 30, 2025
USD ($)
Sep. 30, 2024
USD ($)
Lessee, Lease, Description [Line Items]          
Weighted-average remaining lease term   8 years   8 years  
Weighted average discount rate   4.50%   4.50%  
Interest payments for financing leases   $ 31 $ 30 $ 96 $ 79
Leases not yet commenced   $ 56   $ 56  
UScellular Wireless Assets Operations          
Lessee, Lease, Description [Line Items]          
Lessee leasing arrangements, operating leases, term of contract (years) 30 months        
UScellular Wireless Assets Operations | Master License Agreement          
Lessee, Lease, Description [Line Items]          
Number of towers retained | tower_site 2,100        
Number of towers leased on interim basis | tower_site 1,800        
Operating lease right-of-use assets $ 1,000        
Operating lease liabilities 1,000        
Deferred tax liabilities 261        
Deferred tax assets $ 261        
UScellular Wireless Assets Operations | Purchase Agreement          
Lessee, Lease, Description [Line Items]          
Lessee leasing arrangements, operating leases, term of contract (years) 15 years        
Number of towers to be extended tenancy term | tower_site 600        
Minimum          
Lessee, Lease, Description [Line Items]          
Lessee leasing arrangements, operating leases, term of contract (years)   5 years   5 years  
Lessee, operating lease, renewal term (years)   5 years   5 years  
Lessee leasing arrangements, finance leases, term of contract   3 years   3 years  
Maximum          
Lessee, Lease, Description [Line Items]          
Lessee leasing arrangements, operating leases, term of contract (years)   15 years   15 years  
Lessee, operating lease, renewal term (years)   50 years   50 years  
Lessee leasing arrangements, finance leases, term of contract   5 years   5 years