Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Trading and marketing gains (losses), net	$ (7)	$ 29	$ 145	$ 2
Total operating revenues	1,274	1,798	2,931	3,997
Revenue, Remaining Performance Obligation, Amount	369		$ 369
Revenue, Performance Obligation, Description of Timing			four years
Revenue from contract with customer not within the scope of Topic 606	1,112	822	$ 1,703	1,680
Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	382	488	829	1,184
NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	790	1,171	1,736	2,586
Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	109	110	221	225
Gathering and Processing
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	98	98
Trading and marketing gains (losses), net	(33)	28	68	8
Total operating revenues	618	1,024	1,531	2,312
Gathering and Processing \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	271	363	597	920
Gathering and Processing \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	282	535	669	1,183
Gathering and Processing \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate			197	201
Logistics and Marketing
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	11	12
Trading and marketing gains (losses), net	26	1	77	(6)
Total operating revenues	1,150	1,613	2,508	3,658
Logistics and Marketing \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	355	445	766	1,082
Logistics and Marketing \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	758	1,155	1,641	2,558
Logistics and Marketing \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate			24	24
Eliminations
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate		0
Trading and marketing gains (losses), net	0	0	0	0
Total operating revenues	(494)	(839)	(1,108)	(1,973)
Eliminations \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	(244)	(320)	(534)	(818)
Eliminations \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	$ (250)	$ (519)	$ (574)	(1,155)
Eliminations \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate				$ 0

Revenue from contract with customer not within scope of Topic 606

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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