v3.22.0.1
Receivables and Related Allowance for Credit Losses - EIP Receivables (Details)
$ in Millions
12 Months Ended
Dec. 31, 2021
USD ($)
class
segment
Dec. 31, 2020
USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Customer classes | class 2  
Portfolio segments | segment 2  
EIP receivables, gross $ 8,207 $ 6,213
Unamortized imputed discount (378) (325)
EIP receivables, net of unamortized imputed discount 7,829 5,888
Allowance for credit losses (252) (280)
Equipment installment plan receivables, net 7,577 5,608
Equipment installment plan receivables, net of allowance for credit losses and imputed discount    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Equipment installment plan receivables, net 4,748 3,577
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]    
Equipment installment plan receivables, net $ 2,829 $ 2,031
EIP Receivables Allowance    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Weighted average effective imputed interest rate 5.60% 6.70%