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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Financial Derivative Instruments - Schedule of Location and Amount Recognized in Income by Hedging Relationship (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fuel derivative contracts
Derivative [Line Items]
Amount of loss reclassified from AOCI into income	$ 36
Fuel and oil
Derivative [Line Items]
Total	36	$ 15	$ 110	$ 54
Fuel and oil \| Cash Flow Hedging \| Fuel derivative contracts
Derivative [Line Items]
Amount of loss reclassified from AOCI into income	36	15	110	54
Fuel and oil \| Cash Flow Hedging \| Other
Derivative [Line Items]
Amount of loss reclassified from AOCI into income	0	0	0	0
Other operating expenses
Derivative [Line Items]
Total	2	2	5	6
Other operating expenses \| Cash Flow Hedging \| Fuel derivative contracts
Derivative [Line Items]
Amount of loss reclassified from AOCI into income			0	0
Other operating expenses \| Cash Flow Hedging \| Other
Derivative [Line Items]
Amount of loss reclassified from AOCI into income	$ 2	$ 2	$ 5	$ 6