Acquisitions (Schedule of Merger Related Costs) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Business Acquisition [Line Items]
Transition services			$ 18	$ 0
Professional fees (bank, legal, consulting)	$ 0	$ 3	1	3
Contract buyouts, terminations and transfers	1	0	3	0
Due diligence and environmental	1	0	2	0
Employee-related			1	1
Other			2	0
Merger-related expenses	2	3	27	4
Indigo Natural Resources, LLC
Business Acquisition [Line Items]
Transition services			0	0
Professional fees (bank, legal, consulting)	0	2	0	2
Contract buyouts, terminations and transfers	1	0	1	0
Due diligence and environmental	0	0	1	0
Employee-related			0	0
Other			0	0
Merger-related expenses	1	2	2	2
GEPH Merger
Business Acquisition [Line Items]
Transition services			18
Professional fees (bank, legal, consulting)	0		1
Contract buyouts, terminations and transfers	0		2
Due diligence and environmental	1		1
Employee-related			1
Other			2
Merger-related expenses	$ 1		$ 25
Montage Resources Corporation
Business Acquisition [Line Items]
Transition services				0
Professional fees (bank, legal, consulting)		1		1
Contract buyouts, terminations and transfers		0		0
Due diligence and environmental		0		0
Employee-related				1
Other				0
Merger-related expenses		$ 1		$ 2

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Due Diligence And Environmental Expense

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Transition Services

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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