Accrual For Environmental Loss Contingencies Charges

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- Definition

Environmental loss contingencies adjustment.

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Reclassification of amounts included in asset retirement obligations.

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Reclassification of amounts included in other reserves.

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Reclassification of obligation transferred on separation.

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- Definition

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

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- Definition

Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

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- Definition

Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

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- Definition

Increase (decrease) in the accrual for environmental loss contingencies during the reporting period.

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- Definition

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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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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Amount of cumulative translation gain (loss), before tax, from translating foreign currency financial statements into the reporting currency.

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Contingencies and Commitments - Additional Information - 1 (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Oct. 04, 2016
Loss Contingencies [Line Items]
Remediation reserve balance	$ 280	$ 294
Remediation reserve balance, classified as a current liability	44	36
Increase (decrease) in remediation reserve	16
Payments related to remediation expenses applied against the reserve	25	48	$ 32
Increase (Decrease) in reserves due to effects of foreign currency translation	6	11	5
Reclassification of obligation transferred on separation	6	17	60
Reclassification of amounts included in asset retirement obligations	1	5
Reclassification of amounts included in other reserves				$ 17
Cost of Goods Sold [Member]
Loss Contingencies [Line Items]
Increase (decrease) in remediation reserve	7
Restructuring and Other Charges [Member]
Loss Contingencies [Line Items]
Changes to the remediation reserve due to charges	2
Remediation reserve balance, revision	2
Rockdale Smelter Curtailment [Member]
Loss Contingencies [Line Items]
Increase (decrease) in remediation reserve		1
Remediation reserve adjustment		8
Baie Comeau and Mosjen [Member]
Loss Contingencies [Line Items]
Remediation reserve adjustment		6
Warrick Smelter, Wenatchee Smelter and Point Comfort [Member]
Loss Contingencies [Line Items]
Remediation reserve adjustment		4
Other Sites [Member]
Loss Contingencies [Line Items]
Remediation reserve adjustment		3	13
Changes to the remediation reserve due to charges	9
Suriname Refinery and Permanent Closure [Member]
Loss Contingencies [Line Items]
Increase (decrease) in remediation reserve			39
Remediation reserve adjustment			26
Sherwin [Member]
Loss Contingencies [Line Items]
Remediation reserve balance	38				$ 29
Changes to the remediation reserve due to charges	9
Portovesme Italy [Member]
Loss Contingencies [Line Items]
Remediation reserve balance, revision	2
Several Sites [Member]
Loss Contingencies [Line Items]
Remediation reserve balance	132	150
''Sherwin, TX Site [Member]
Loss Contingencies [Line Items]
Remediation reserve balance	38	29
Increase (decrease) in remediation reserve	$ 9
Alcoa Corporation [Member] \| Warrick Smelter, Wenatchee Smelter and Point Comfort [Member]
Loss Contingencies [Line Items]
Remediation reserve adjustment		$ 4	$ 26