Derivative Instruments And Hedging Activities Derivatives and Hedging Instruments Gains Losses due to Settlements Hedge Ineffectiveness (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Trading Activity, Gains and Losses, Net [Line Items]
Derivative, Net Hedge Ineffectiveness Gain (Loss)	$ 1,658	$ (2,160)
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	(18,570)	86,988
Derivative Instruments, Gain (Loss) Recognized in Income	4,422	5,490
Sales [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Derivative, Net Hedge Ineffectiveness Gain (Loss)	(133)
Derivative Instruments, Gain (Loss) Recognized in Income	49,180	(25,331)
Cost of Sales [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Derivative, Net Hedge Ineffectiveness Gain (Loss)	1,244
Derivative Instruments, Gain (Loss) Recognized in Income	(40,769)	29,317
Operating Expense [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Derivative, Net Hedge Ineffectiveness Gain (Loss)	547	(2,160)
Derivative Instruments, Gain (Loss) Recognized in Income	(3,989)	1,504
Commodity Contract [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Derivative Instruments, change in fair value	(14,148)	92,478
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(4,692)	(5,760)
Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring	$ 270	$ 270

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Amount of gain (loss) from the ineffectiveness of the hedge.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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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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