v3.20.4
Property, Equipment and Right-of-Use Assets - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Property, Equipment and Right-of-Use Assets [Line Items]      
Depreciation expense including amortization for capital leases $ 400 $ 336 $ 209
Operating lease amortization expense $ 123 $ 99  
Weighted-average remaining lease term of operating lease 9 years 1 month 6 days 9 years 6 months  
Weighted-average discount rate for operating leases 2.70% 2.90%  
Lease office space rental expense     94
Lease expense     $ 20