Amount of amortization expense attributable to debt issuance 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 net cash inflow or cash outflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

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Amount of cash outflow for payment of an obligation from a 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
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Financing Obligations
Unamortized fees	$ 13,000		$ 14,400
Amortization expenses	1,347	$ 1,390
Sale-lease transactions \| Sale Leaseback Sites
Financing Obligations
Unamortized fees	500		600
Credit Agreement
Financing Obligations
Unamortized fees	3,900		4,800
Working Capital Facility
Supplemental Cash Flow Information [Abstract]
Borrowing from credit facility	751,400	669,100
Payments on credit facility	(657,500)	(645,200)
Net borrowings from (payments on) credit facility	93,900	23,900
Non Working Capital Facility
Supplemental Cash Flow Information [Abstract]
Borrowing from credit facility		384,000
Payments on credit facility		(199,400)
Net borrowings from (payments on) credit facility		$ 184,600
Senior Notes
Financing Obligations
Unamortized fees	$ 8,600		$ 9,000