Investing Activities (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019		Jun. 30, 2020	Jun. 30, 2019
Schedule of Equity Method Investments [Line Items]
Gain on disposition of equity-method investments (1)	$ 0	$ 122	[1]	$ 0	$ 122	[1]
Other investing income (loss) - net	1	124		4	125
Impairment of equity-method investments	0	(2)		938	72
Proceeds from dispositions of equity-method investments				0	485
Equity earnings (losses)	108	87		130	$ 167
Jackalope Gas Gathering Services LLC [Member]
Schedule of Equity Method Investments [Line Items]
Gain on disposition of equity-method investments (1)		$ 122
Equity Method Investment, Ownership Percentage		50.00%			50.00%
Proceeds from dispositions of equity-method investments		$ 485
Rocky Mountain Midstream Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity earnings (losses)				(78)
Other Income [Member]
Schedule of Equity Method Investments [Line Items]
Other investing income (loss) - net	$ 1	$ 2		4	$ 3
Impairment Of Equity-Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Impairment of equity-method investments				$ 938	$ 72

[1] In April 2019, we sold our 50 percent equity-method interest in Jackalope for $485 million in cash, resulting in a gain on the disposition of $122 million.