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v3.20.2

Fair Value Measurements - Quantitative Information about Level 3 Fair Value (Details) - Significant unobservable inputs (Level 3) - Fuel derivatives - Measurement Input, Option Volatility | Sep. 30, 2020
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Minimum | Fourth quarter 2020 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.27 |
Minimum | 2021 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.29 |
Minimum | 2022 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.26 |
Minimum | Beyond 2022 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.23 |
Weighted Average | Fourth quarter 2020 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.41 | [1]
Weighted Average | 2021 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.33 | [1]
Weighted Average | 2022 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.27 | [1]
Weighted Average | Beyond 2022 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.25 | [1]
Maximum | Fourth quarter 2020 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.47 |
Maximum | 2021 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.44 |
Maximum | 2022 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.30 |
Maximum | Beyond 2022 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Derivative Asset, Measurement Input | 0.26 |
[1] | Implied volatility weighted by the notional amount (barrels of fuel) that will settle in respective period.

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- Definition Value of input used to measure derivative asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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