Derivatives Financial Instruments - Derivative Income Statement Location (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Derivative [Line Items]
Total gain (loss)		$ 14	$ (6)
Product sales
Derivative [Line Items]
Realized gain (loss)		0	0
Total gain (loss)		0	0
Purchased product costs
Derivative [Line Items]
Realized gain (loss)		(1)	(2)
Total gain (loss)		14	(6)
Cost of revenues
Derivative [Line Items]
Realized gain (loss)		0	0
Total gain (loss)		0	0
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives and Commodity Contracts	[1]	15	(4)	[2]
Not Designated as Hedging Instrument [Member] | Product sales
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives and Commodity Contracts		0	0
Not Designated as Hedging Instrument [Member] | Purchased product costs
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives and Commodity Contracts		15	(4)
Not Designated as Hedging Instrument [Member] | Cost of revenues
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives and Commodity Contracts		$ 0	$ 0

[1] See below for the reconciliation from Segment Adjusted EBITDA to net income.

[2] Financial information for the first quarter of 2019 has been retrospectively adjusted for the acquisition of ANDX. See Notes 1 and 3.