Property, Plant and Equipment - Additional Information (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Property, Plant and Equipment [Line Items]      
Depreciation expense $ 508 $ 497 $ 460
Provision for depreciation, percentage of aggregate average depreciable asset 2.96% 3.09% 3.07%
Investment tax credit $ 164    
Other Current Assets      
Property, Plant and Equipment [Line Items]      
Investment tax credit, receivable 16    
Other Long-term Assets      
Property, Plant and Equipment [Line Items]      
Investment tax credit, receivable $ 148