Gain (Loss) on Corporate Restructuring

No definition available.

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- Definition

Separation Adjustments

+ References

No definition available.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- 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
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- Definition

The number of positions eliminated during the period as a result of restructuring activities.

+ References

No definition available.

+ Details

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in the restructuring reserve related to foreign currency translation (gain) loss and other increases (decreases).

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- Definition

Amount of restructuring charges, remediation cost, and asset impairment loss.

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Restructuring and Other Charges - Restructuring Reserve (Details) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020 USD ($) employee claimants	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Restructuring Reserve [Roll Forward]
Beginning balance			$ 21	$ 4	$ 21	$ 4
Cash payments			(13)			(15)
Restructuring charges			27			32
Other			(7)			0
Ending balance	$ 30		30			21
Restructuring and other charges	(77)	$ (38)	(58)	(40)
Separation-related adjustments (A)	314		314
Restructuring and other charges	$ 77	38	58	40
Number of employees separated \| employee	410
Forecast
Restructuring Reserve [Roll Forward]
Cash payments					(7)
Hard Alloy Extrusions Plant in South Korea
Restructuring Reserve [Roll Forward]
Gain (Loss) on Disposition of Business			25
Aluminum Rolling Mill in Brazil
Restructuring Reserve [Roll Forward]
Gain (Loss) on Disposition of Business			25
Operating segments
Restructuring Reserve [Roll Forward]
Restructuring and other charges	$ (15)	(26)	(6)	(37)
Rolled Products [Member]
Restructuring Reserve [Roll Forward]
Restructuring and other charges	(7)	(2)	(16)	(8)
Building and Construction Systems [Member]
Restructuring Reserve [Roll Forward]
Restructuring and other charges	(5)	(24)	(6)	(29)
Extrusions [Member]
Restructuring Reserve [Roll Forward]
Restructuring and other charges	(3)	0	(28)	0
Corporate Segment
Restructuring Reserve [Roll Forward]
Restructuring and other charges	(62)	(12)	(64)	(3)
Layoff costs
Restructuring Reserve [Roll Forward]
Beginning balance			20	1	20	1
Cash payments			(11)			(12)
Restructuring charges			25			30
Other			(7)			1
Ending balance	29		29			20
Restructuring and other charges	(17)
Separation-related adjustments (A)			2
Layoff costs \| Building and Construction System and Extrustions [Member]
Restructuring Reserve [Roll Forward]
Restructuring and other charges	$ (8)
Number of employees separated \| claimants	140
Other costs
Restructuring Reserve [Roll Forward]
Beginning balance			1	3	$ 1	3
Cash payments			(2)			(3)
Restructuring charges			2			2
Other			0			(1)
Ending balance	$ 1		1			$ 1
Restructuring and other charges	(2)		(4)	(2)
Separation-related adjustments (A)			0
Other costs \| Building and Construction System and Extrustions [Member]
Restructuring Reserve [Roll Forward]
Restructuring and other charges	(11)
Spin-off
Restructuring Reserve [Roll Forward]
Restructuring and other charges	$ 0	$ (12)	(2)	$ (3)
Separation-related adjustments (A)			$ 2