This amount represents the purchase price of the business acquisition.

No definition available.

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- Definition

Amount of consideration receivable due to the entity from the former owners of the acquiree to settle partnership accounts.

+ References

No definition available.

+ Details

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- Definition

Amount of consideration received, consisting of the economic adjustment due to the entity from the former owners of the acquiree. The related adjustments include metal off-take and aluminum sales agreements, cash funding and management fee adjustments, as well as adjustments for inventory and transition services.

+ References

No definition available.

+ Details

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- Definition

Amount of consideration received, consisting of the working capital and other adjustments due to the entity from the former owners of the acquiree. The other adjustments include post-employment benefit payments, business interruption premium share, and reimbursement related to the election of certain tax positions for the acquisition.

+ References

No definition available.

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- Definition

Amount of funding related to the 414(l) liability in excess of the GAAP pension liability incurred by the acquirer as part of consideration transferred in a business combination.

+ References

No definition available.

+ Details

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- Definition

Amount of acquirer's share of the unfunded GAAP pension liability incurred by the acquirer as part of consideration transferred in a business combination.

+ References

No definition available.

+ Details

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- Definition

Amount of pension funding liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

No definition available.

+ Details

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

+ Details

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

+ Details

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 25

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 35

-Paragraph 1

-Subparagraph b

-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

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- Definition

The revenues and gains recognized recorded for each transaction with the acquiree that is recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(1)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(2)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Business acquisitions Acquisition of Mt. Holly smelter narrative (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		0 Months Ended	12 Months Ended	1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 01, 2014	Dec. 31, 2014	Apr. 30, 2015
Business Acquisition [Line Items]
Unrealized gain on fair value of contingent consideration	$ 6,527	$ 0
Mt. Holly Smelter [Member]
Business Acquisition [Line Items]
Purchase price			67,500
Purchase price cash paid				53,831
Acquisition costs	313			1,087
Pension funding total			46,546
Pension funding for unfunded GAAP liability			15,704
Pension funding for 414(l) liability			30,842
Contingent consideration, high			22,500
Contingent consideration, low			12,500
Contingent consideration at acquisition date			13,780
Unrealized gain on fair value of contingent consideration	6,527
Consideration receivable, economic adjustment			10,000
Consideration receivable, working capital and other			2,324
Settlement of partnership accounts			23,172
Remeasurement of existing equity investment			56,723
Gain on remeasurement of equity investment				1,318
Mt. Holly Smelter [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Purchase price cash paid					$ 38,162