Amount of amortization expense attributable to debt issuance costs.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt and Financing Obligations - Deferred Financing Fees, Supplemental Cash Flow (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Supplemental Cash Flow Information [Abstract]
Additional financing fees	$ 800		$ 800
Unamortized fees	22,500		22,500		$ 27,700
Amortization expenses	2,000	$ 1,900	6,032	$ 5,593
Credit Agreement
Supplemental Cash Flow Information [Abstract]
Unamortized fees	7,100		7,100		10,000
Working Capital Facility
Supplemental Cash Flow Information [Abstract]
Borrowing from revolving credit facility			2,660,500	2,032,600
Payments on revolving credit facility			(2,787,600)	(2,021,500)
Net (payments on) borrowings from working capital revolving credit facility			(127,100)	11,100
Non Working Capital Facility
Supplemental Cash Flow Information [Abstract]
Borrowing from revolving credit facility			276,500	39,700
Payments on revolving credit facility			(235,500)	(81,900)
Net (payments on) borrowings from working capital revolving credit facility			41,000	$ (42,200)
Sale Leaseback Transaction
Supplemental Cash Flow Information [Abstract]
Unamortized fees	300		300		400
Senior Notes
Supplemental Cash Flow Information [Abstract]
Unamortized fees	$ 15,100		$ 15,100		$ 17,300
6.875% senior notes due 2029
Supplemental Cash Flow Information [Abstract]
Stated interest rate (as a percent)	6.875%		6.875%		6.875%
8.250% senior notes due 2032
Supplemental Cash Flow Information [Abstract]
Stated interest rate (as a percent)	8.25%		8.25%		8.25%
7.125% senior notes due 2033
Supplemental Cash Flow Information [Abstract]
Stated interest rate (as a percent)	7.125%		7.125%		7.125%