Asset Retirement obligations.

No definition available.

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- Definition

Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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Asset Retirement Obligations - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2022	Dec. 31, 2021
Asset Retirement Obligations [Line Items]
Current liability	$ 116		$ 117	$ 116
Liabilities incurred			224	101
Reversals of previously recorded liabilities			(12)	(6)
Restructuring and Other Charges [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			34	23
Restructuring and Other Charges [Member] \| Closed Tennessee Site [Member]
Asset Retirement Obligations [Line Items]
Reversals of previously recorded liabilities				5
Cost of Goods Sold [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			72
Magnesium Smelter Facility in Addy [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			15
Bauxite Residue Areas [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			81	28
Mine Areas [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			79	30
Spent Pot Lining Treatment and Disposal [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			28	17
Bauxite Residue Areas Related to Water Management [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			18
Demolition Projects [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred			$ 3
Wenatchee Smelter [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred	$ 16
Lake Charles Anode Facility [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred		$ 5
Landfill Closure [Member]
Asset Retirement Obligations [Line Items]
Liabilities incurred				$ 5