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Fair Value Measurements - Quantative Information about Level 3 Fair Value (Details) - Option Model - Implied Volatility - Fuel derivatives | Mar. 31, 2017
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Second quarter 2017 |
Quantitative Information About Level 3 |
Fair Value Measurement Range, Minimum | 15.00%
Fair Value Measurement Range, Maximum | 29.00%
Third quarter 2017 |
Quantitative Information About Level 3 |
Fair Value Measurement Range, Minimum | 21.00%
Fair Value Measurement Range, Maximum | 30.00%
Fourth quarter 2017 |
Quantitative Information About Level 3 |
Fair Value Measurement Range, Minimum | 22.00%
Fair Value Measurement Range, Maximum | 30.00%
2018 |
Quantitative Information About Level 3 |
Fair Value Measurement Range, Minimum | 20.00%
Fair Value Measurement Range, Maximum | 29.00%
2019 |
Quantitative Information About Level 3 |
Fair Value Measurement Range, Minimum | 17.00%
Fair Value Measurement Range, Maximum | 24.00%

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