Derivative Instruments And Hedging Activities (Summary Of Balance Sheet Locations And Related Fair Values Of Outstanding Derivative Instruments) (Details) (USD $) In Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Derivative [Line Items]
Commodity price swap contracts, Fair Value	$ 122,682
Commodity price swap contracts, Offsetting Amount	122,682
Variable-to-fixed interest rate swap contract, Offsetting Amount	14,800
Other Long-Term Liabilities [Member]
Derivative [Line Items]
Variable-to-fixed interest rate swap contract, Fair Value	7,378	10,026
Prepayments And Other Current Assets [Member]
Derivative [Line Items]
Commodity price swap contracts, Fair Value	122,682
Commodity price swap contracts, Fair Value	8,115
Accrued Liabilities [Member]
Derivative [Line Items]
Commodity price swap contracts, Offsetting Amount	100,139
Commodity price swap contracts, Fair Value		38
Derivatives not designated as hedge liability, Fair Value	1,184	497
Cost Of Products Sold (Decrease) [Member]
Derivative [Line Items]
Commodity price swap contracts, Offsetting Amount	362
Commodity price swap contracts, Offsetting Amount	8,115
Cost Of Products Sold (Increase) [Member]
Derivative [Line Items]
Derivatives not designated as hedge liability, Offsetting Amount	1,184	497
Accumulated Other Comprehensive Loss [Member]
Derivative [Line Items]
Commodity price swap contracts, Offsetting Amount	22,181
Variable-to-fixed interest rate swap contract, Offsetting Amount	7,378	10,026
Commodity price swap contracts, Offsetting Amount		$ 38

Fair value of all asset derivatives designated as cash flow hedging instruments.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 10

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

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Gain included in earnings for the period from the change in fair value of derivative instruments not designated as hedging instruments.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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Loss included in earnings for the period from the change in fair value of derivative instruments not designated as hedging instruments.

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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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Amount of unrealized gain (loss) related to the increase (decrease) in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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Amount of unrealized gain (loss) arising from the change in fair value of price risk derivatives designated as cash flow hedging instruments recorded in accumulated other comprehensive income in the period, before taxes, to the extent that the cash flow hedge is determined to be effective.

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