Comprehensive Income (Loss) 2 Parentheticals (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Comprehensive Income Loss [Line Items]
Change in fair value of interest rate hedges tax	$ (6,891)	$ (1,308)	$ (7,757)	$ (3,614)
Reclassification of unrealized loss (gain) on interest rate hedges tax	2,253	2,250	4,481	4,554
Change in fair value of commodity hedges tax	194	(390)	(365)	9,613
Relcassification of unrealized (gain) loss on commodity hedges into earnings tax	(1,678)	(1,830)	(3,310)	(2,272)
Reclassification of net actuarial loss and prior service credit relating to pension and other postretirement benefits into earnings tax	568	551	1,142	1,102
Change in other comprehensive income (loss) from equity investments tax	$ 21	$ 22	$ 43	$ 44

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Tax effect of the change in accumulated gains and losses from commodity hedges designated and qualifying as the effective portion of cash flow hedges.

+ Details

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- Definition

Tax effect of change in accumulated gains and losses from equity investments

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- Definition

Tax effect of the change in accumulated gains and losses from interest rate hedges designated and qualifying as the effective portion of cash flow hedges.

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Tax effect on reclassification adjustment for accumulated gains and losses from commodity hedges designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

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Tax effect on reclassification adjustment for accumulated gains and losses from interest rate hedges designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

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For each annual statement of income presented, the tax effect of the net gain (loss) recognized in other comprehensive income that is a reclassification adjustment of other comprehensive income as a result of being recognized as a component of net periodic benefit cost for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 25
-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.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e640-108580

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