Segments and Related Information - Schedule of Reportable Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Segments and Related Information
Number of reportable segments not disclosed flag			true
Reportable segment information
Sales	$ 1,078.0	$ 1,100.4	$ 3,098.5	$ 3,239.9
Cost of sales	704.3	1,095.5	2,849.8	3,092.7
Gross profit	373.7	4.9	248.7	147.2
Adjusted EBITDA	69.6	59.8	162.8	162.7
Reconciling items to net income (loss):
Depreciation and amortization	50.7	45.3	145.3	136.6
LCM / LIFO (gain) loss	5.1	9.4	3.1	8.9
(Gain) loss on sale of business	6.4		(55.8)
Interest expense	53.6	57.7	165.0	175.3
Debt extinguishment costs	(0.5)		47.2	0.3
Unrealized gain on derivatives	(2.0)	(13.6)	(9.1)	(52.3)
RINs incurrence gain (expense)	(303.1)	10.0	(257.4)	24.5
RINs mark-to-market loss (gain)	(20.8)	32.8	145.1	(26.1)
Other non-recurring expenses (income)	(5.3)	12.1	2.1	72.1
Equity-based compensation and other items	9.5	7.0	6.1	4.4
Income tax (benefit) expense	(41.4)	0.7	(40.8)	1.4
Noncontrolling interest adjustments	4.0	(1.0)	8.5	(1.1)
Net income (loss)	313.4	(100.6)	3.5	(181.3)
Capital expenditures	23.5	19.4	62.9	69.6
PP&E, net	1,362.0	1,453.3	1,362.0	1,453.3	$ 1,438.8
External customers
Reportable segment information
Sales	1,078.0	1,100.4	3,098.5	3,239.9
Eliminations
Reportable segment information
Sales	(5.2)	(6.4)	(15.2)	(18.6)
Eliminations | Inter-segment sales
Reportable segment information
Sales	(5.2)	(6.4)	(15.2)	(18.6)
Specialty Products and Solutions | Operating Segments
Reportable segment information
Sales	684.1	720.3	1,972.0	2,160.1
Cost of sales	402.8	711.7	1,729.7	2,015.1
Gross profit	276.3	2.3	227.4	126.7
Adjusted EBITDA	80.2	50.7	203.3	170.6
Reconciling items to net income (loss):
Depreciation and amortization	21.5	17.4	56.4	53.1
LCM / LIFO (gain) loss	1.4	4.2	5.6	1.3
Interest expense	7.1	5.6	16.4	17.3
Debt extinguishment costs	(0.4)		(0.4)	0.1
Unrealized gain on derivatives	(2.0)	(13.6)	(9.1)	(52.3)
RINs incurrence gain (expense)	(192.9)	8.1	(158.6)	20.4
RINs mark-to-market loss (gain)	(16.7)	22.6	99.4	(16.9)
Capital expenditures	21.4	9.4	47.8	41.0
PP&E, net	333.0	355.7	333.0	355.7
Specialty Products and Solutions | Operating Segments | External customers
Reportable segment information
Sales	679.1	714.0	1,957.1	2,141.8
Specialty Products and Solutions | Operating Segments | Inter-segment sales
Reportable segment information
Sales	5.0	6.3	14.9	18.3
Performance Brands | Operating Segments
Reportable segment information
Sales	79.9	80.4	242.8	256.4
Cost of sales	61.2	57.6	179.7	186.0
Gross profit	18.5	22.7	62.8	70.1
Adjusted EBITDA	13.2	13.6	42.5	41.1
Reconciling items to net income (loss):
Depreciation and amortization	1.2	2.2	4.4	6.5
LCM / LIFO (gain) loss	1.7	0.8	2.5	0.8
(Gain) loss on sale of business	6.3		(58.1)
Interest expense	0.1		0.1	0.1
Capital expenditures		0.2	0.7	0.8
PP&E, net	29.7	32.0	29.7	32.0
Performance Brands | Operating Segments | External customers
Reportable segment information
Sales	79.7	80.3	242.5	256.1
Performance Brands | Operating Segments | Inter-segment sales
Reportable segment information
Sales	0.2	0.1	0.3	0.3
Montana/Renewables | Operating Segments
Reportable segment information
Sales	319.2	306.1	898.9	842.0
Cost of sales	240.3	326.2	940.4	891.6
Gross profit	78.9	(20.1)	(41.5)	(49.6)
Adjusted EBITDA	(5.8)	14.6	(24.5)	9.9
Reconciling items to net income (loss):
Depreciation and amortization	27.9	25.5	84.0	76.3
LCM / LIFO (gain) loss	2.0	4.4	(5.0)	6.8
Interest expense	15.4	15.7	48.8	48.7
Debt extinguishment costs	(0.1)		47.5
RINs incurrence gain (expense)	(110.2)	1.9	(98.8)	4.1
RINs mark-to-market loss (gain)	(4.1)	10.2	45.7	(9.2)
Capital expenditures	2.1	8.9	13.9	25.1
PP&E, net	994.6	1,061.1	994.6	1,061.1
Montana/Renewables | Operating Segments | External customers
Reportable segment information
Sales	319.2	306.1	898.9	842.0
Corporate | Operating Segments
Reportable segment information
Adjusted EBITDA	(18.0)	(19.1)	(58.5)	(58.9)
Reconciling items to net income (loss):
Depreciation and amortization	0.1	0.2	0.5	0.7
(Gain) loss on sale of business	0.1		2.3
Interest expense	31.0	36.4	99.7	109.2
Debt extinguishment costs			0.1	0.2
Capital expenditures		0.9	0.5	2.7
PP&E, net	$ 4.7	$ 4.5	$ 4.7	$ 4.5