Derivatives (Narrative) (Details) (USD $) In Millions	6 Months Ended
Jul. 02, 2011
Notional amount of commodity derivatives	12.6 million MMBTUs
Notional value of foreign currency derivatives	$ 11.3
Natural Gas Forward Purchase Contracts [Member]
Net deferred losses on cash flow hedges on natural gas forward purchase contracts that are included in accumulated other comprehensive income that are expected to be reclassified into earnings during the next twelve months	$ 36.6
Net deferred losses on cash flow hedges reclassification period	within the next 12 months

The estimated net amount of existing gains (losses) on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(2)

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- Definition

Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

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- Definition

Description of the transactions or other events that will result in the reclassification into earnings of gains (losses) reported in accumulated other comprehensive income. May include the time period over which gains (losses) will be reclassified to earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(2)

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- Definition

Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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