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Hedging Activities (Narrative) (Details) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | 12 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|---|
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Mar. 31, 2013
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Mar. 31, 2012
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Sep. 30, 2011
financial_institution
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Dec. 31, 2012
financial_institution
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Dec. 31, 2011
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Jul. 31, 2012
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Feb. 29, 2012
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Dec. 31, 2010
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Feb. 28, 2010
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| General Discussion of Derivative Instruments and Hedging Activities [Abstract] | |||||||||
| Number of financial institutions | 4 | 4 | |||||||
| Expected to reclassify out of accumulated other comprehensive income in next 12 months | $ 9,100 | $ 9,660 | |||||||
| Loss on fair value hedge ineffectiveness | 200 | 300 | 144 | ||||||
| Gain on fair value hedge ineffectiveness | $ 25 | ||||||||
| Production barrels per day (bbls/day) | 4,000 | 2,000 | 3,000 | 2,000 | 2,300 | 3,000 | |||
| Forward contract sale, price per barrel | 107.29 | 86.96 | 109.73 | 108.00 | 58.24 | 54.81 | |||
| Delivered percentage of production under fixed price swaps | 46.00% | ||||||||
| X | ||||||||||
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- Definition
Delivered percentage of production under fixed price swaps. No definition available.
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| X | ||||||||||
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- Definition
Number Of Financial Institutions No definition available.
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| X | ||||||||||
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- Definition
Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
The estimated net amount of existing gains or 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
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| X | ||||||||||
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- Definition
The price per barrel of the notional amount of the derivative contract expressed in nonmonetary units. For example, the price per barrel specified in a fuel oil forward purchase contract. No definition available.
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| X | ||||||||||
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- Definition
Gain recognized in earnings during the reporting period representing the amount of the fair value hedges' ineffectiveness. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Details
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| X | ||||||||||
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- Definition
Loss recognized in earnings during the reporting period representing the amount of the fair value hedges' ineffectiveness. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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