v3.25.2
Receivables and Related Allowance for Credit Losses - Schedule of Unamortized Imputed Discount and Allowance for Credit Losses for Equipment Installment Plan Receivables (Details) - USD ($)
$ in Millions
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Allowance for credit losses and imputed discount, beginning of period $ 990 $ 934
Bad debt expense 588 537
Write-offs (592) (538)
Change in imputed discount on short-term and long-term EIP receivables 50 45
Impact on the imputed discount from sales of EIP receivables (88) (99)
Allowance for credit losses and imputed discount, end of period 948 879
Accounts Receivable Allowance    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Allowance for credit losses and imputed discount, beginning of period 176 161
Bad debt expense 290 254
Write-offs (294) (255)
Allowance for credit losses and imputed discount, end of period 172 160
EIP Receivables Allowance    
Financing Receivable, Allowance for Credit Loss [Roll Forward]    
Allowance for credit losses and imputed discount, beginning of period 814 773
Bad debt expense 298 283
Write-offs (298) (283)
Change in imputed discount on short-term and long-term EIP receivables 50 45
Impact on the imputed discount from sales of EIP receivables (88) (99)
Allowance for credit losses and imputed discount, end of period $ 776 $ 719