v3.21.2
Goodwill, Spectrum License Transactions and Other Intangible Assets - Narrative (Details)
$ in Millions
1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended
Apr. 01, 2020
USD ($)
Mar. 31, 2021
USD ($)
license
Oct. 31, 2020
USD ($)
Jun. 30, 2021
USD ($)
Jun. 30, 2020
USD ($)
Jun. 30, 2021
USD ($)
Jun. 30, 2020
USD ($)
Dec. 31, 2020
USD ($)
Goodwill [Line Items]                
Goodwill from acquisition               $ 9,405
Purchase of spectrum licenses       $ 8 $ 745 $ 8,930 $ 844  
Amortization expense for intangible assets       $ 295 $ 387 661 $ 411  
Licensing Agreements | Auction 107                
Goodwill [Line Items]                
Number of licenses | license   142            
Aggregate purchase price   $ 9,300            
Purchase of spectrum licenses   $ 8,900 $ 438          
Expected remaining cost           $ 1,200    
Sprint                
Goodwill [Line Items]                
Goodwill from acquisition $ 9,400              
Sprint | Favorable lease (asset)                
Goodwill [Line Items]                
Finite-lived, fair value $ 745              
Weighted average useful life 18 years              
Sprint | Unfavorable spectrum leases                
Goodwill [Line Items]                
Finite-lived, fair value $ 125              
Weighted average useful life 19 years              
Sprint | Customer relationships                
Goodwill [Line Items]                
Finite-lived, fair value $ 4,900              
Weighted average useful life 8 years              
Sprint | Spectrum Licenses                
Goodwill [Line Items]                
Fixed period 15 years