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Operating Leases (Narrative) (Details) $ in Thousands, Engine in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) Engine | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) Engine Aircraft | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Lessee Lease Description [Line Items] |  |  |  |  |
Operating lease right-of-use assets, net | $ 794,443 |  | $ 794,443 |  | $ 809,174
Lease liabilities, net | 858,346 |  | $ 858,346 |  | $ 867,426
Number of aircraft engines | Aircraft |  |  | 8 |  |
Net book value of lease assets | 35,200 |  | $ 35,200 |  |
Lease income | $ 1,200 | $ 8,600 | $ 7,700 | $ 18,200 |
Minimum [Member] | Office Space and Office Equipment [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Operating leases remaining lease term |  |  | 1 year |  |
Maximum [Member] | Office Space and Office Equipment [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Operating leases remaining lease term |  |  | 14 years |  |
Other Income [Member] | Four Aircraft Engine [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Number of engines sold | Engine | 4 |  |  |  |
Net book value | $ 33,000 |  | $ 33,000 |  |
Gain loss on sale of aircraft engines | 9,900 |  |  |  |
Other Income [Member] | Ten Aircraft Engine [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Number of engines sold | Engine |  |  | 10 |  |
Net book value | $ 86,000 |  | $ 86,000 |  |
Gain loss on sale of aircraft engines |  |  | $ 41,900 |  |

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- Definition Amount, after accumulated depreciation, of long-lived, depreciable flight asset owned and right-of-use asset from finance lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-1 + Details
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