v3.20.1
Fair Value Measurement - FV of Commodity Derivatives (Details) - USD ($)
$ in Millions
Mar. 31, 2020
Dec. 31, 2019
Offsetting Derivative Assets [Abstract]    
Assets - gross amounts recognized $ 399 $ 322
Assets - amounts without right of setoff 2 3
Assets - gross amounts 397 319
Assets - gross amounts offset 213 193
Assets - net amounts presented 184 126
Assets - cash collateral 5 4
Assets - net amounts 179 122
Offsetting Derivative Liabilities [Abstract]    
Liabilities - gross amounts recognized 359 311
Liabilities - amounts without right of setoff 2 4
Liabilities - gross amounts recognized 357 307
Liabilities - gross amounts offset 213 193
Liabilities - net amounts presented 144 114
Liabilities - cash collateral 56 12
Liabilities - net amounts $ 88 $ 102