Derivative Financial Instruments - Changes in Fair Value of Commodity Derivative Contracts (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
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| Gain Loss On Derivative Instruments Net Pretax [Abstract] | ||||
| Derivative loss | $ 1,078 | $ 13,079 | $ 1,078 | $ 20,571 |
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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