v3.8.0.1
Debt - Schedule Of Aggregate Maturities Of Debt (Details) - USD ($)
$ in Millions
Dec. 31, 2017
Dec. 31, 2016
Debt Disclosure [Abstract]    
2018 $ 4  
2019 16  
2020 4  
2021 1,451  
2022 1,151  
Thereafter 2,203  
Total 4,829  
Fair value of outstanding debt $ 4,751 $ 4,676