v3.24.4
Debt - Narrative (Details)
12 Months Ended
Apr. 01, 2020
USD ($)
instrument
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Jan. 31, 2025
USD ($)
Jul. 25, 2023
USD ($)
Debt Instrument [Line Items]          
Effective interest rate   4.10% 4.00%    
Weighted-average debt outstanding during period   $ 78,300,000,000 $ 75,400,000,000    
Carrying value   78,265,000,000 75,018,000,000    
Short-term debt   4,068,000,000 3,619,000,000    
Letters of credit, amount outstanding   152,000,000 238,000,000    
Spectrum Financing Special Purpose Entity          
Debt Instrument [Line Items]          
Lease payments (per month) $ 165,000,000        
Sprint          
Debt Instrument [Line Items]          
Total outstanding obligation   1,300,000,000 2,200,000,000    
Revolving Credit Facility          
Debt Instrument [Line Items]          
Credit facility outstanding balance   0 0    
4.738% Series 2018-1 A-1 Notes due 2025 | Sprint          
Debt Instrument [Line Items]          
Principal Issuances 2,100,000,000        
5.152% Series 2018-1 A-2 Notes due 2028 | Sprint          
Debt Instrument [Line Items]          
Short-term debt   368,000,000      
Senior Notes          
Debt Instrument [Line Items]          
Principal Issuances   $ 7,650,000,000      
Senior Notes | Sprint          
Debt Instrument [Line Items]          
Principal Issuances $ 3,900,000,000        
Senior Notes | Senior Secured Notes Issued in 2021 | Minimum          
Debt Instrument [Line Items]          
Term preceding maturity date   1 month      
Senior Notes | Senior Secured Notes Issued in 2021 | Maximum          
Debt Instrument [Line Items]          
Term preceding maturity date   3 years      
Senior Notes | 3.360% Senior Secured Series 2016-1 A-1 Notes due 2021 | Sprint          
Debt Instrument [Line Items]          
Payable term 5 years        
Principal Issuances $ 3,500,000,000        
Interest rate, stated percentage   3.36%      
Securitization program amount $ 7,000,000,000        
Number of instruments | instrument 2        
Senior Notes | 4.738% Series 2018-1 A-1 Notes due 2025          
Debt Instrument [Line Items]          
Interest rate, stated percentage   4.738%      
Senior Notes | 4.738% Series 2018-1 A-1 Notes due 2025 | Sprint          
Debt Instrument [Line Items]          
Interest rate, stated percentage   4.738%      
Short-term debt   $ 131,000,000      
Senior Notes | 5.152% Series 2018-1 A-2 Notes due 2028 | Sprint          
Debt Instrument [Line Items]          
Principal Issuances   $ 1,800,000,000      
Interest rate, stated percentage   5.152%      
Line of Credit | Revolving Credit Facility          
Debt Instrument [Line Items]          
Financing commitment, amount   $ 7,500,000,000      
Line of Credit | Letter of Credit          
Debt Instrument [Line Items]          
Financing commitment, amount   1,500,000,000      
Line of Credit | Bridge Loan          
Debt Instrument [Line Items]          
Financing commitment, amount   $ 500,000,000      
ABS Notes          
Debt Instrument [Line Items]          
Expected weighted average life   2 years 6 months      
Payable term   2 years      
Carrying value   $ 1,570,000,000      
Gross EIP receivables   2,000,000,000.0      
Commercial Paper          
Debt Instrument [Line Items]          
Financing commitment, amount         $ 2,000,000,000
Short-term debt   $ 0 $ 0    
Loans Payable | Subsequent Event          
Debt Instrument [Line Items]          
Financing commitment, amount       $ 1,000,000,000