v3.22.0.1

Restructuring and Other Charges - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($) employee segment	Dec. 31, 2019 USD ($)	Dec. 31, 2019 segment	Dec. 31, 2019 employee
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$ 624	$ 188	$ 87
Cash payments, restructuring	15	27	15
Layoff costs
Restructuring Cost and Reserve [Line Items]
Cash payments, restructuring	10	24	12
Allocated costs, ParentCo
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		2	7
Other Items
Restructuring Cost and Reserve [Line Items]
Cash payments, restructuring	5	$ 3	3
2019 Restructuring Programs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			87
Expected number of employees separated		370		480	480
2019 Restructuring Programs | Rolled Products
Restructuring Cost and Reserve [Line Items]
Expected number of employees separated | employee					240
2019 Restructuring Programs | Building and Construction Systems
Restructuring Cost and Reserve [Line Items]
Expected number of employees separated | employee					190
2019 Restructuring Programs | Extrusions
Restructuring Cost and Reserve [Line Items]
Expected number of employees separated | employee					50
2019 Restructuring Programs | Disposals | Texarkana Rolling Mill and Cast House
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			(20)
2019 Restructuring Programs | Layoff costs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			30
Cash payments, restructuring	$ 3	$ 9	11
2019 Restructuring Programs | Allocated costs, ParentCo
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			7
2019 Restructuring Programs | Other Items
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			7
2019 Restructuring Programs | Asset Impairments | Aluminum Rolling Mill in Brazil
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			53
2019 Restructuring Programs | Impairment of Carrying Value of Tradename
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges			$ 10
2020 Restructuring Programs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		$ 188
Expected number of employees separated | segment	500	550
2020 Restructuring Programs | Building and Construction System and Extrustions
Restructuring Cost and Reserve [Line Items]
Expected number of employees separated | employee		90
2020 Restructuring Programs | COVID-19
Restructuring Cost and Reserve [Line Items]
Expected number of employees separated | employee		460
2020 Restructuring Programs | Settlement of Certain Employee Retirement Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$ 584	$ 199
2020 Restructuring Programs | Contingent Consideration Related to Disposal | Texarkana Rolling Mill and Cast House
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		(25)
2020 Restructuring Programs | Disposals | Extrusions Plant in South Korea and Aluminum Rolling Mill in Brazil
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		(25)
2020 Restructuring Programs | Costs Related to Planned Closures and Related Organizations | Building and Construction System and Extrustions
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		21
2020 Restructuring Programs | Layoff costs
Restructuring Cost and Reserve [Line Items]
Cash payments, restructuring	5	15
2020 Restructuring Programs | Layoff costs | Building and Construction System and Extrustions
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		5
2020 Restructuring Programs | Layoff costs | COVID-19
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		18
2020 Restructuring Programs | Reversal of Reserve
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		(14)
2020 Restructuring Programs | Reversal of Reserve, Environmental Matter
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		(5)
2020 Restructuring Programs | Legacy Non-Income Tax Matters in Brazil
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		4
2020 Restructuring Programs | Allocated costs, ParentCo
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		2
2020 Restructuring Programs | Other Items
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges		$ 8
2021 Restructuring Programs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$ 624
2021 Restructuring Programs | Extrusions
Restructuring Cost and Reserve [Line Items]
Number of employees separated | segment	115
2021 Restructuring Programs | Settlement of Certain Employee Retirement Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$ 584
2021 Restructuring Programs | Disposals | Aluminum Rolling Mill in Itapissuma, Brazil
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	1
2021 Restructuring Programs | Costs Related to Planned Closures and Related Organizations
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	34
2021 Restructuring Programs | Layoff costs
Restructuring Cost and Reserve [Line Items]
Cash payments, restructuring	2
2021 Restructuring Programs | Reversal of Reserve
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	4
2021 Restructuring Programs | Other Items
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	2
2021 Restructuring Programs | Idling of Operations | Extrusions
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	7
2021 Restructuring Programs | Legacy Tax Matters
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	4
2021 Restructuring Programs | Legal Matters, Other
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$ 4

X

- Definition

Restructuring, Settlement And Impairment Provisions, Including Gain (Loss) On Disposition Of Assets And Business

+ References

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X

- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3367-108585

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