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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Financial Derivative Instruments - Location and Amount Recognized in Income by Hedging Relationship (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Cash Flow Hedging
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	$ (182)	$ 352	$ 71	$ (452)
Cash Flow Hedging \| Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	(175)	354	78	(438)
Cash Flow Hedging \| Interest rate derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	(7)	(2)	(7)	(14)
Fuel and oil
Derivative [Line Items]
Derivatives designated as hedging instruments	(52)	(195)	(93)	(703)
Fuel and oil \| Cash Flow Hedging \| Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	(52)	(195)	(93)	(703)
Fuel and oil \| Cash Flow Hedging \| Interest rate derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	0	0	0	0
Other operating expenses
Derivative [Line Items]
Derivatives designated as hedging instruments	2	2	5	5
Other operating expenses \| Cash Flow Hedging \| Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	0	0	0	0
Other operating expenses \| Cash Flow Hedging \| Interest rate derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	$ 2	$ 2	$ 5	$ 5