Conditional Asset Retirement Obligation, Measurement Input

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- Definition

ExpectedPeriodRelatedToRemediationExpendituresForEnvironmentalContingencies

+ References

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- Definition

Period For Final Feasibility Study

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- Definition

Time period within which recorded estimate of its obligation may change.

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

The difference between the maximum amount of estimated loss and the amount recorded as of the balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 05
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=99385795&loc=d3e12631-108344

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- Definition

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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No definition available.

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Commitments and Contingencies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Environmental Contingency
Liability for conditional asset retirement obligations	$ 7,200,000	$ 6,700,000	$ 6,500,000	$ 6,300,000
Environmental accrual	$ 16,800,000	$ 18,700,000	$ 17,000,000.0	$ 16,900,000
Expected period related to remediation expenditures for environmental contingencies period	30 years
Potential increase in environmental costs	$ 11,600,000
Time period within which recorded estimate of its obligation may change	12 months
Minimum
Environmental Contingency
Period for final feasibility study	20 months
Maximum
Environmental Contingency
Period for final feasibility study	26 months
Alcoa Warrick LLC [Member]
Environmental Contingency
Liability for conditional asset retirement obligations	$ 0
Weighted-average Credit-adjusted Risk-free Rate
Environmental Contingency
Weighted-average credit-adjusted risk-free rate (percent)	8.70%	8.70%