v2.4.0.6

Derivative Instruments and Hedging Activities - Additional Information (Detail) (Commodity Contract, Cost of sales, USD $) | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011
Commodity Contract | Cost of sales |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Recognized loss in cost of sales on commodity contracts not designated as hedging instruments | $ 1,471,000 | $ 1,295,000

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- Details
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Period Type: | duration

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- Definition Net gain (loss) from the increase (decrease) in fair value of derivative instrument not designated as hedging instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 45 -Subparagraph b(1)(b) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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