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.

No definition available.

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- Definition

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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- Definition

For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related costs which have been expensed.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Acquisitions and Dispositions - Non-Recurring Restructuring and Transition-Related Costs (Details) - Concho Resources Incorporated [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2021
Business Acquisition [Line Items]
Transaction Cost		$ 157	$ 157
Restructuring Cost	$ 52		209
Total Costs			366
Production and operating expenses [Member]
Business Acquisition [Line Items]
Restructuring Cost			110
Total Costs			110
Selling, general and administrative expenses [Member]
Business Acquisition [Line Items]
Transaction Cost			135
Restructuring Cost			64
Total Costs			199
Exploration expenses [Member]
Business Acquisition [Line Items]
Transaction Cost			18
Restructuring Cost			4
Total Costs			22
Taxes other than income taxes [Member]
Business Acquisition [Line Items]
Transaction Cost			4
Restructuring Cost			2
Total Costs			6
Other expenses [Member]
Business Acquisition [Line Items]
Transaction Cost			0
Restructuring Cost			29
Total Costs			$ 29