Annual report pursuant to Section 13 and 15(d)

Property and Equipment, Net (Narrative) (Details)

v3.20.4
Property and Equipment, Net (Narrative) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Property, Plant and Equipment [Abstract]      
Depreciation expense $ 61 $ 71 $ 68