v3.20.2
Fair Value Measurement - FV of Commodity Derivatives (Details) - USD ($)
$ in Millions
Sep. 30, 2020
Dec. 31, 2019
Offsetting Derivative Assets [Abstract]    
Assets - gross amounts recognized $ 301 $ 322
Assets - amounts without right of setoff 1 3
Assets - gross amounts 300 319
Assets - gross amounts offset 204 193
Assets - net amounts presented 96 126
Assets - cash collateral 5 4
Assets - net amounts 91 122
Offsetting Derivative Liabilities [Abstract]    
Liabilities - gross amounts recognized 277 311
Liabilities - amounts without right of setoff 0 4
Liabilities - gross amounts recognized 277 307
Liabilities - gross amounts offset 204 193
Liabilities - net amounts presented 73 114
Liabilities - cash collateral 7 12
Liabilities - net amounts $ 66 $ 102