v3.20.4
Leases - Leased Wireless Devices (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Apr. 01, 2020
Dec. 31, 2019
Property, Plant and Equipment [Line Items]      
Accumulated depreciation $ (42,395)   $ (33,118)
Property and equipment, net $ 41,175   21,984
Leased wireless devices      
Property, Plant and Equipment [Line Items]      
Useful life (in years) 8 months    
Property, plant and equipment $ 6,989   1,139
Accumulated depreciation (2,170)   (407)
Property and equipment, net $ 4,819   $ 732
Leased wireless devices | Sprint      
Property, Plant and Equipment [Line Items]      
Property and equipment, net   $ 5,800