v3.22.0.1
Receivables and Related Allowance for Credit Losses - Unamortized Imputed Discount and Allowance for Credit Losses (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Allowance for credit losses and imputed discount, beginning of period $ 799 $ 460 $ 516
Bad debt expense 452 602 307
Write-offs, net of recoveries (527) (380) (332)
Change in imputed discount on short-term and long-term EIP receivables 187 171 136
Impact on the imputed discount from sales of EIP receivables (135) (145) (167)
Allowance for credit losses and imputed discount, end of period 776 799 460
Cumulative Effect, Period of Adoption, Adjustment      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Allowance for credit losses and imputed discount, beginning of period 0 91 0
Allowance for credit losses and imputed discount, end of period   0 91
Accounts Receivable Allowance      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Allowance for credit losses and imputed discount, beginning of period 194 61 67
Bad debt expense 231 338 77
Write-offs, net of recoveries (279) (205) (83)
Allowance for credit losses and imputed discount, end of period 146 194 61
Accounts Receivable Allowance | Cumulative Effect, Period of Adoption, Adjustment      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Allowance for credit losses and imputed discount, beginning of period 0 0 0
Allowance for credit losses and imputed discount, end of period   0 0
EIP Receivables Allowance      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Allowance for credit losses and imputed discount, beginning of period 605 399 449
Bad debt expense 221 264 230
Write-offs, net of recoveries (248) (175) (249)
Change in imputed discount on short-term and long-term EIP receivables 187 171 136
Impact on the imputed discount from sales of EIP receivables (135) (145) (167)
Allowance for credit losses and imputed discount, end of period 630 605 399
EIP Receivables Allowance | Cumulative Effect, Period of Adoption, Adjustment      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Allowance for credit losses and imputed discount, beginning of period $ 0 91 0
Allowance for credit losses and imputed discount, end of period   $ 0 $ 91