v3.22.2.2

Restructuring and Other Charges - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($) claimant	Dec. 31, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)	$ 112	$ 14	$ 119	$ 612
Cash payments, restructuring			5		$ 15
Environmental remediation, payments	1		7
UNITED STATES | Pension benefits
Restructuring Cost and Reserve [Line Items]
Defined Benefit Plan, Benefit Obligation, Payment for Settlement	15	5	15	24
Fusina, Italy
Restructuring Cost and Reserve [Line Items]
Environmental remediation, payments			1
Extrusions
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges	92		92
Impairment, Long-Lived Asset, Held-for-Use	90
Other miscellaneous costs
Restructuring Cost and Reserve [Line Items]
Cash payments, restructuring			2		5
Layoff costs
Restructuring Cost and Reserve [Line Items]
Cash payments, restructuring			3		$ 10
2022 Restructuring Programs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)	112		119
2022 Restructuring Programs | Legal Matters, Other
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)			5
2022 Restructuring Programs | One-time Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)			1
2022 Restructuring Programs | Idling of Operations | Extrusions
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)			2
2022 Restructuring Programs | Other miscellaneous costs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)	$ 5		$ 5
2021 Restructuring Programs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)		14		$ 612
2021 Restructuring Programs | Extrusions
Restructuring Cost and Reserve [Line Items]
Number of employees separated | claimant				115
2021 Restructuring Programs | Legal Matters, Other
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)		3		$ 3
2021 Restructuring Programs | One-time Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)		5		573
2021 Restructuring Programs | Disposals | Aluminum Rolling Mill in Itapissuma, Brazil
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)				1
2021 Restructuring Programs | Idling of Operations | Extrusions
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)		3		6
2021 Restructuring Programs | Reversal of Reserve [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)		1		3
2021 Restructuring Programs | Other miscellaneous costs
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)		1		2
2021 Restructuring Programs | Facility Closing
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)				34
2021 Restructuring Programs | Legacy Tax Matters
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges (E)		$ 3		$ 4

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