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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		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Cash Flow Hedging
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	$ 125	$ (147)	$ 252	$ (804)
Cash Flow Hedging \| Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	126	(140)	252	(792)
Cash Flow Hedging \| Interest rate derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	(1)	(7)	0	(12)
Fuel and oil
Derivative [Line Items]
Derivatives designated as hedging instruments	(14)	(306)	(42)	(508)
Fuel and oil \| Cash Flow Hedging \| Fuel derivative contracts
Derivative [Line Items]
Amount of (gain) reclassified from AOCI into income	(14)	(306)	(42)	(508)
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	3	3
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	$ 3	$ 3