Financial Instruments and Derivatives - Additional Information (Detail) $ in Thousands, BTU in Millions	12 Months Ended
Dec. 31, 2015 USD ($) BTU T t	Dec. 31, 2014 USD ($)
Derivative [Line Items]
Anticipated usage percentage of natural gas covered by a swap contract for the first succeeding fiscal year	79.00%
Anticipated usage percentage of natural gas covered by swap contract	19.00%
Anticipated usage percentage of aluminum covered by a swap contract for the first succeeding fiscal year	40.00%
Fair value of commodity cash flow hedges	$ (3,611)	$ (6,086)
Commodity gain (loss) expected to be reclassified to the income statement during the next 12 months	(3,265)
Fair value of foreign currency cash flow hedges	(4,612)	(3,526)
Cash flow hedge gain (loss) reclassified from accumulated other comprehensive loss and netted against the carrying value of the assets	528	2
Foreign currency gain (loss) expected to be reclassified to the income statement during the next 12 months	(4,515)
Total fair value of other derivatives not designated as hedging instruments	$ (2,180)	$ (1,098)
Natural gas swaps
Derivative [Line Items]
Approximate amount of commodity covered by swap contracts outstanding in MMBTUs \| BTU	6.2
Aluminum Swaps
Derivative [Line Items]
Approximate amount of commodity covered by swap contracts outstanding in metric tons \| t	2,983
Containers
Derivative [Line Items]
Approximate amount of commodity covered by swap contracts outstanding in metric tons \| T	2,640
Anticipated usage percentage of short tons covered by a swap contract for the first succeeding fiscal year	1.00%

Anticipated Usage Percentage of Aluminum Covered by Swap Contract First Succeeding Fiscal Year.

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- Definition

Anticipated usage percentage of natural gas covered by swap contract year one.

+ References

No definition available.

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- Definition

Anticipated usage percentage of natural gas covered by swap contract year two.

+ References

No definition available.

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- Definition

Cash flow hedge gain reclassified from accumulated other comprehensive loss and netted against the carrying value of the assets.

+ References

No definition available.

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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

Nominal energy measure used to calculate payments on a derivative instrument.

+ References

No definition available.

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- Definition

Nominal mass used to calculate payments on a derivative instrument.

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- Definition

The percentage of expected requirements covered by the aggregate notional amount of derivative contracts expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract as a percentage of expected need.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of all foreign currency derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(b),(c)(1)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

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- Definition

The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

Net fair value of all derivative instruments not designated as a hedging instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13495-108611

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- Definition

Fair value as of the balance sheet date of all price risk derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

The estimated net amount of unrealized gains or losses on price risk cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

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