v3.25.2
Receivables and Related Allowance for Credit Losses - Schedule of Equipment Installment Plan Receivables (Details)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2025
USD ($)
segment
class
Dec. 31, 2024
USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Portfolio segments | segment 2  
Customer classes | class 2  
EIP receivables, gross $ 6,977 $ 7,402
Unamortized imputed discount (486) (524)
EIP receivables, net of unamortized imputed discount 6,491 6,878
Allowance for credit losses (290) (290)
EIP receivables, net of allowance for credit losses and imputed discount 6,201 6,588
Equipment installment plan receivables, net of allowance for credit losses and imputed discount    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
EIP receivables, net of allowance for credit losses and imputed discount 4,226 4,379
Equipment installment plan receivables due after one year, net of allowance for credit losses and imputed discount    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
EIP receivables, net of allowance for credit losses and imputed discount $ 1,975 $ 2,209
EIP Receivables Allowance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Weighted average effective imputed interest rate 11.20% 11.10%