v3.25.4

Significant Accounting Policies - Variable Interest Entities (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Sep. 30, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024
--- | --- | --- | --- | --- | --- | --- | --- | ---
Variable Interest Entity |  |  |  |  |  |  |  |
Cash and cash equivalents | $ 6,476 |  |  | $ 5,649 |  |  |  |
Prepaid expenses and other current assets | 37,963 |  |  | 63,651 |  |  |  |
Property, plant and equipment, net | 2,102,797 |  |  | 2,066,847 |  |  |  |
Accrued expenses and other payables | (139,168) |  |  | (135,233) |  |  |  |
Current maturities of long-term debt | (8,918) |  |  | (8,805) |  |  |  |
Long-term debt, net | (2,924,455) |  |  | (2,961,703) |  |  |  |
Redeemable noncontrolling interests | (506) |  |  | (424) |  |  |  |
Partnership's equity in VIEs | 119,495 | $ 123,825 | $ 142,454 | 145,849 | $ 162,592 | $ 185,335 | $ 213,993 | $ 448,070
Nonrelated Party |  |  |  |  |  |  |  |
Variable Interest Entity |  |  |  |  |  |  |  |
Accounts payable | (451,663) |  |  | (461,980) |  |  |  |
Related Party |  |  |  |  |  |  |  |
Variable Interest Entity |  |  |  |  |  |  |  |
Accounts receivable-affiliates | 419 |  |  | 730 |  |  |  |
Accounts payable | (1) |  |  | (102) |  |  |  |
Variable Interest Entity, Primary Beneficiary |  |  |  |  |  |  |  |
Variable Interest Entity |  |  |  |  |  |  |  |
Cash and cash equivalents | 17 |  |  | 14 |  |  |  |
Prepaid expenses and other current assets | 180 |  |  | 108 |  |  |  |
Property, plant and equipment, net | 15,489 |  |  | 15,984 |  |  |  |
Accrued expenses and other payables | (168) |  |  | (190) |  |  |  |
Current maturities of long-term debt | (1,918) |  |  | (1,805) |  |  |  |
Long-term debt, net | (8,372) |  |  | (9,818) |  |  |  |
Redeemable noncontrolling interests | (506) |  |  | (424) |  |  |  |
Partnership's equity in VIEs | 4,996 |  |  | 3,980 |  |  |  |
Variable Interest Entity, Primary Beneficiary | Nonrelated Party |  |  |  |  |  |  |  |
Variable Interest Entity |  |  |  |  |  |  |  |
Accounts payable | (145) |  |  | (24) |  |  |  |
Variable Interest Entity, Primary Beneficiary | Related Party |  |  |  |  |  |  |  |
Variable Interest Entity |  |  |  |  |  |  |  |
Accounts receivable-affiliates | $ 419 |  |  | $ 135 |  |  |  |
Parent Co |  |  |  |  |  |  |  |
Variable Interest Entity |  |  |  |  |  |  |  |
Parent ownership percentage in aviation entities | 90.00% |  |  |  |  |  |  |
Noncontrolling Interest |  |  |  |  |  |  |  |
Variable Interest Entity |  |  |  |  |  |  |  |
Noncontrolling interest ownership percentage in aviation entities | 10.00% |  |  |  |  |  |  |

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