Derivatives and Risk Management Activities - Financial Impact (Details) - Derivatives Not Designated as a Hedge - Commodity Derivatives - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Impact of derivative activities recognized in earnings
Total gain/(loss) on derivatives recognized in net income	$ (32)	$ 153	$ (17)	$ 395
Supply and Logistics segment revenues
Impact of derivative activities recognized in earnings
Total gain/(loss) on derivatives recognized in net income	(37)	149	(22)	380
Field operating costs
Impact of derivative activities recognized in earnings
Total gain/(loss) on derivatives recognized in net income	$ 5	$ 4	$ 5	$ 15