Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Trading and marketing gains (losses), net	$ 152	$ (27)
Total operating revenues	1,657	2,199
Revenue, Remaining Performance Obligation, Amount	$ 383
Revenue, Performance Obligation, Description of Timing	four years
Revenue from contract with customer not within the scope of Topic 606	$ 591	858
Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	447	696
NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	946	1,415
Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	112	115
Gathering and Processing
Disaggregation of Revenue [Line Items]
Trading and marketing gains (losses), net	101	(20)
Total operating revenues	913	1,288
Gathering and Processing \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	326	557
Gathering and Processing \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	387	648
Gathering and Processing \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	99	103
Logistics and Marketing
Disaggregation of Revenue [Line Items]
Trading and marketing gains (losses), net	51	(7)
Total operating revenues	1,358	2,045
Logistics and Marketing \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	411	637
Logistics and Marketing \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	883	1,403
Logistics and Marketing \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	13	12
Eliminations
Disaggregation of Revenue [Line Items]
Trading and marketing gains (losses), net	0	0
Total operating revenues	(614)	(1,134)
Eliminations \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	(290)	(498)
Eliminations \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	$ (324)	(636)
Eliminations \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate		$ 0

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

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-Publisher FASB
-Name Accounting Standards Codification
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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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