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Other (Income) Expenses, Net - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Other Non Operating Income Expense [Line Items]
Net (gain) loss from asset sales			$ (124)	$ (176)
Former Eastalco Site Sale And Warrick Rolling Mill [Member]
Other Non Operating Income Expense [Line Items]
Net (gain) loss from asset sales	$ (93)		$ (120)
Gum Springs [Member]
Other Non Operating Income Expense [Line Items]
Net (gain) loss from asset sales		$ (1)		$ (181)

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- Definition

Other non operating income expense.

+ References

No definition available.

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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