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Operating Leases - Aircraft (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 USD ($) engine aircraft | Dec. 31, 2024 USD ($) aircraft engine | Dec. 31, 2023 USD ($) engine aircraft
Lessee, Lease, Description [Line Items] |  |  |
Gains recognized on sale-leaseback transactions | $ | $ 302 | $ 294 | $ 147
Aircraft and spare engines |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Number of leases | aircraft | 176 |  |
Aircraft and spare engines | Minimum |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Remaining lease terms (in months and years) | 2 years |  |
Aircraft and spare engines | Maximum |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Remaining lease terms (in months and years) | 12 years |  |
Aircraft and spare engines | A320neo |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Third party lessors, number of aircraft | aircraft | 0 | 0 | 10
Aircraft and spare engines | A320neo | Aircraft Sale Leaseback |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Third party lessors, number of aircraft | aircraft | 19 | 23 | 11
Aircraft Engine |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Number of leases | engine | 61 |  |
Number of engines dependent on usage-based metrics | engine | 17 |  |
Aircraft Engine | Aircraft Sale Leaseback |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Leaseback transactions, number of engines | engine | 18 | 5 | 4
Aircraft Engine | Minimum |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Remaining lease terms (in months and years) | 1 month |  |
Aircraft Engine | Maximum |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Remaining lease terms (in months and years) | 12 years |  |
Aircraft and Aircraft Engines |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Gains recognized on sale-leaseback transactions | $ | $ 302 | $ 294 | $ 147

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- Definition Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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