Amount of amortization expense attributable to debt issuance costs.

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The amount of debt issuance costs that were incurred during a noncash or partial noncash transaction.

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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		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Financing Obligations
Unamortized fees	$ 15,700		$ 15,700		$ 18,800
Amortization expenses	1,300	$ 1,200	4,084	$ 3,810
Sale-lease transactions \| Sale Leaseback Sites
Financing Obligations
Unamortized fees	600		600		600
Credit Agreement
Financing Obligations
Deferred financing fees capitalized			1,000
Unamortized fees	5,700		5,700		7,500
Working Capital Facility
Supplemental Cash Flow Information [Abstract]
Borrowing from credit facility			1,641,800	1,573,700
Payments on credit facility			(1,996,500)	(1,505,200)
Net borrowings from (payments on) credit facility			(354,700)	68,500
Non Working Capital Facility
Supplemental Cash Flow Information [Abstract]
Borrowing from credit facility			423,000	10,000
Payments on credit facility			(367,400)	(88,600)
Net borrowings from (payments on) credit facility			55,600	$ (78,600)
Senior Notes
Financing Obligations
Unamortized fees	$ 9,400		$ 9,400		$ 10,700