Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Net Sales	$ 538.8	$ 450.5	$ 1,553.3	$ 1,282.8
Costs and expenses:
Cost of sales	(454.8)	(398.2)	(1,332.0)	(1,160.9)
Selling, general and administrative expenses	(32.9)	(28.3)	(99.6)	(82.5)
Other Cost and Expense, Operating	2.2	10.2	8.5	55.1
Total operating costs and expenses	489.9	436.7	1,440.0	1,298.5
Income (loss) from operations	48.9	13.8	113.3	(15.6)
Interest Expense, Net	(8.0)	(8.9)	(27.3)	(27.5)
Debt retirement costs	0.0	(0.5)	(0.5)	(0.5)
Other Nonoperating Income (Expense)	(1.4)	(2.8)	(4.3)	(7.8)
Total non-operating expense	(9.4)	(12.2)	(32.1)	(35.7)
Income (loss) before income taxes	39.5	1.7	81.2	(51.4)
Income tax provision (benefit)	18.9	(0.3)	29.3	(13.8)
Net income (loss)	$ 20.6	$ 1.9	$ 51.9	$ (37.6)
Net income (loss) per common share:
Basic (in dollars per share)	$ 1.23	$ 0.12	$ 3.09	$ (2.25)
Diluted (in dollars per share)	$ 1.21	$ 0.11	$ 3.04	$ (2.25)
Weighted Average Number of Shares Outstanding, Basic	16,754	16,687	16,777	16,689
Weighted Average Number of Shares Outstanding, Diluted	17,093	16,971	17,085	16,689