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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 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 + Details
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