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Business acquisitions - Acquisition of Mt. Holly smelter narrative other units (Details) - Mt. Holly Smelter [Member] t in Thousands	Dec. 01, 2014 employee t	Oct. 23, 2014
Business Acquisition [Line Items]
Remaining percentage acquired in step acquisition		50.30%
Percentage of ownership after step acquisition	100.00%
Employees	600
Mt Holly primary aluminum capacity (tonnes) | t	231

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- Definition

Percentage of ownership at the acquisition date as a result of the business combination.

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- Definition

Annual production capacity of primary aluminum (in tonnes).

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- Definition

Number of persons employed by the Entity

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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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- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

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