(Gain) Loss from Divestitures, Asset Impairments and Unusual Items, Net (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Asset Impairments and Unusual Items
(Gain) loss from divestitures, asset impairments and unusual items, net	$ 17	$ 17
Increase in legal accruals		19
Asset impairments		6
Gain (loss) on sale of assets		$ 8
San Jacinto Waste Pits [Member]
Asset Impairments and Unusual Items
Revisions in estimates and interest rate assumptions	$ 17

Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The increase (decrease) during the reporting period in other expenses incurred but not yet paid.

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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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The aggregate amount of asset impairment charges, (gains) and losses related to the divestiture of businesses and unusual items incurred during an accounting period.

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