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Fair Value Measurements - Quantitative Information about Level 3 Fair Value (Details) - Option Model - Implied Volatility - Fuel derivatives | Dec. 31, 2016
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2017 |
Quantitative Information About Level 3 [Line Items] |
Fair Value Measurement Range, Minimum | 16.00%
Fair Value Measurement Range, Maximum | 36.00%
2018 |
Quantitative Information About Level 3 [Line Items] |
Fair Value Measurement Range, Minimum | 20.00%
Fair Value Measurement Range, Maximum | 31.00%
2019 |
Quantitative Information About Level 3 [Line Items] |
Fair Value Measurement Range, Minimum | 18.00%
Fair Value Measurement Range, Maximum | 24.00%

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- Definition Maximum range used in level 3 fair value calculation + References No definition available. + Details
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- Definition Minimum range used in level 3 fair value calculation + References No definition available. + Details
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