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Financial Derivative Instruments - Premiums for Fuel Derivative Contracts (Details) - Fuel derivative contracts - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Designated as Hedging Instrument | Fuel and oil |  |
Derivative [Line Items] |  |
Premium expense recognized in income on derivatives | $ 26 | $ 14
Not Designated as Hedging Instrument | Other (gains)/losses, net |  |
Derivative [Line Items] |  |
Premium expense recognized in income on derivatives | $ 0 | $ 11

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- Definition The premium (cost) of a hedge, expensed during the period. + References No definition available. + Details
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- Details
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- Details
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- Details
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