Revenue - Passenger Revenue Breakout (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Operating revenue	$ 6,329	$ 5,706
Passenger
Disaggregation of Revenue [Line Items]
Operating revenue	5,712	5,105
Passenger non-loyalty
Disaggregation of Revenue [Line Items]
Operating revenue	4,680	4,082
Passenger loyalty - air transportation
Disaggregation of Revenue [Line Items]
Operating revenue	799	825
Passenger ancillary sold separately
Disaggregation of Revenue [Line Items]
Operating revenue	$ 233	$ 198

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.

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 280
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-Topic 280
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147479806/606-10-50-4

+ Details