Long-Term Debt - Summary of Long Term Debt (Details) - USD ($) $ in Millions		9 Months Ended	12 Months Ended
		Sep. 30, 2024	Dec. 31, 2023	Mar. 07, 2024	Jun. 27, 2023
Summary of Long-term debt
MRL Term Loan Credit Agreement		$ 73.9	$ 74.4
MRL asset financing arrangements		372.5	384.6
Finance lease obligations, at various interest rates, interest and principal payments monthly through June 2028		2.9	3.0
Less unamortized debt issuance costs	[1]	(16.2)	(16.1)
Less unamortized discounts		(2.8)	(3.5)
Total debt		2,059.3	1,885.4
Less current portion of long-term debt		400.3	55.7
Total long-term debt		1,659.0	1,829.7
Accumulated amortization, deferred debt issuance costs		30.3	26.6
Revolving Credit Facility
Summary of Long-term debt
Long-term line of credit		$ 225.9	$ 136.7
Weighted average interest rate during period		7.70%	6.80%
MRL Revolving Credit Agreement
Summary of Long-term debt
Borrowings under senior notes			$ 13.0
Weighted average interest rate during period		7.30%	6.90%
9.25% Senior Notes due July 2024
Summary of Long-term debt
Borrowings under senior notes			$ 179.0
Fixed interest rate			9.25%	9.25%
Effective interest rate			9.50%
11.00% Senior Notes due 2025
Summary of Long-term debt
Borrowings under senior notes		$ 363.5	$ 413.5
Fixed interest rate		11.00%	11.00%	11.00%
Effective interest rate		11.40%	11.40%
8.125% Senior Notes due July 2027
Summary of Long-term debt
Borrowings under senior notes		$ 325.0	$ 325.0
Fixed interest rate		8.125%	8.125%
Effective interest rate		8.30%	8.30%
9.75% July 2028, Notes
Summary of Long-term debt
Borrowings under senior notes		$ 325.0	$ 325.0
Fixed interest rate		9.75%			9.75%
Effective interest rate		10.20%
9.25% July 2029, Notes
Summary of Long-term debt
Borrowings under senior notes		$ 200.0
Fixed interest rate		9.25%
Effective interest rate		9.40%
9.25% Senior Secured First Lien Notes due 2029 (the "2029 Secured Notes")
Summary of Long-term debt
Fixed interest rate				9.25%
Shreveport terminal asset financing arrangement
Summary of Long-term debt
Asset financing arrangement		$ 44.9	$ 50.8
Montana terminal asset financing arrangement
Summary of Long-term debt
Asset financing arrangement		34.7
Montana refinery asset financing arrangement
Summary of Long-term debt
Asset financing arrangement		$ 110.0

[1] Deferred debt issuance costs are being amortized by the effective interest rate method over the lives of the related debt instruments. These amounts are net of accumulated amortization of $30.3 million and $26.6 million at September 30, 2024 and December 31, 2023, respectively.