Parenthetical Data to Stockholders' Equity (Tables) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Parenthetical data to equity note
Changes in commodity derivatives, taxes	$ 4,165	$ (1,206)	$ 1,578	$ (2,194)
Foreign currency translation adjustment, taxes	$ (582)	$ (1,112)	$ (770)	$ (1,648)

Total tax effect of the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges after taxes. The change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

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