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Derivative Instruments - Summary of Changes of Fuel Price Derivatives which Have Been Recorded in Net Realized And Unrealized Gains (Losses) on Derivative Instruments (Details) (USD $)
In Thousands, unless otherwise specified |
12 Months Ended | ||
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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| Derivative Instruments and Hedging Activities Disclosure [Abstract] | |||
| Realized (losses) | $ (2,115)us-gaap_DerivativeGainLossOnDerivativeNet | $ (4,223)us-gaap_DerivativeGainLossOnDerivativeNet | $ (10,641)us-gaap_DerivativeGainLossOnDerivativeNet |
| Unrealized gains (losses) | 48,327us-gaap_UnrealizedGainLossOnDerivatives | (5,628)us-gaap_UnrealizedGainLossOnDerivatives | (1,724)us-gaap_UnrealizedGainLossOnDerivatives |
| Net realized and unrealized gains (losses) on derivative instruments | $ 46,212us-gaap_GainLossOnPriceRiskDerivativesNet | $ (9,851)us-gaap_GainLossOnPriceRiskDerivativesNet | $ (12,365)us-gaap_GainLossOnPriceRiskDerivativesNet |
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- Definition
Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The aggregate net gain (loss) on price risk derivatives included in earnings in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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