Financial Derivative Instruments - Premiums for Fuel Derivative Contracts (Details) - Fuel derivative contracts - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Designated as Hedging Instrument \| Fuel and oil
Derivative [Line Items]
Premium expense recognized in income on derivatives	$ 26	$ 14	$ 53	$ 29
Not Designated as Hedging Instrument \| Other (gains)/losses, net
Derivative [Line Items]
Premium expense recognized in income on derivatives	$ 0	$ 10	$ 0	$ 21

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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