Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Trading and marketing gains (losses), net	$ 11	$ (1)	$ 156	$ 1
Total operating revenues	1,586	1,699	4,517	5,696
Revenue, Remaining Performance Obligation, Amount	356		$ 356
Revenue, Performance Obligation, Description of Timing			four years
Revenue from contract with customer not within the scope of Topic 606	303	704	$ 2,006	2,384
Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	459	518	1,288	1,702
NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	1,007	1,081	2,743	3,667
Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	109	101	330	326
Gathering and Processing
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	97	91
Trading and marketing gains (losses), net	(26)	14	42	22
Total operating revenues	857	916	2,388	3,228
Gathering and Processing \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	330	374	927	1,294
Gathering and Processing \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	456	437	1,125	1,620
Gathering and Processing \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate			294	292
Logistics and Marketing
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	13	11
Trading and marketing gains (losses), net	37	(15)	114	(21)
Total operating revenues	1,438	1,509	3,946	5,167
Logistics and Marketing \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	437	461	1,203	1,543
Logistics and Marketing \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	951	1,052	2,592	3,610
Logistics and Marketing \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate			37	35
Eliminations
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	(1)	(1)
Trading and marketing gains (losses), net	0	0	0	0
Total operating revenues	(709)	(726)	(1,817)	(2,699)
Eliminations \| Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	(308)	(317)	(842)	(1,135)
Eliminations \| NGLs and Condensate [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate	$ (400)	$ (408)	(974)	(1,563)
Eliminations \| Transportation, Processing and Other [Member]
Disaggregation of Revenue [Line Items]
Sales of natural gas, NGLs and condensate			$ (1)	$ (1)

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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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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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