Significant Accounting Policies - Variable Interest Entities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024
Variable Interest Entity
Cash and cash equivalents	$ 8,659		$ 5,649
Prepaid expenses and other current assets	32,483		63,651
Property, plant and equipment, net	2,034,103		2,066,847
Accrued expenses and other payables	(126,614)		(135,233)
Current maturities of long-term debt	(8,880)		(8,805)
Long-term debt, net	(2,903,746)		(2,961,703)
Redeemable noncontrolling interests	(488)		(424)
Partnership's equity in VIEs	123,825	$ 142,454	145,849	$ 185,335	$ 213,993	$ 448,070
Nonrelated Party
Variable Interest Entity
Accounts payable	(391,290)		(461,980)
Related Party
Variable Interest Entity
Accounts receivable-affiliates	237		730
Accounts payable	(1)		(102)
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity
Cash and cash equivalents	101		14
Prepaid expenses and other current assets	274		108
Property, plant and equipment, net	15,757		15,984
Accrued expenses and other payables	(169)		(190)
Current maturities of long-term debt	(1,880)		(1,805)
Long-term debt, net	(8,865)		(9,818)
Redeemable noncontrolling interests	(488)		(424)
Partnership's equity in VIEs	4,890		3,980
Variable Interest Entity, Primary Beneficiary | Nonrelated Party
Variable Interest Entity
Accounts payable	(77)		(24)
Variable Interest Entity, Primary Beneficiary | Related Party
Variable Interest Entity
Accounts receivable-affiliates	$ 237		$ 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%