STATEMENTS OF CONSOLIDATED CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net income	$ 15.9	$ 8.1
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of property, plant and equipment	24.9	24.0
Amortization of definite-lived intangible assets	1.4	3.5
Amortization of debt premium and debt issuance costs	0.5	0.6
Deferred income taxes	4.1	2.0
Non-cash equity compensation	3.4	4.0
(Gain) loss on disposition of property, plant and equipment	(15.0)	0.3
Changes in operating assets and liabilities, net of effects of acquisition:
Trade and other receivables	(36.9)	(97.1)
Contract assets	5.7	(11.7)
Inventories	(12.3)	(26.9)
Prepaid expenses and other current assets	(1.2)	(2.5)
Accounts payable	(22.6)	92.9
Accrued liabilities	10.3	6.5
Long-term assets and liabilities, net	1.5	(2.3)
Net cash (used in) provided by operating activities	(20.3)	1.4
Cash flows from investing activities:
Capital expenditures	(41.1)	(28.3)
Proceeds from disposition of property, plant and equipment	15.2
Net cash used in investing activities	(25.9)	(28.3)
Cash flows from financing activities:
Borrowings under the Revolving Credit Facility	119.5
Repayment of borrowings under the Revolving Credit Facility	(80.1)
Repayment of finance lease	(0.6)	(0.5)
Cancellation of shares to cover employees' tax withholdings upon vesting of non-vested shares	(1.3)	(1.9)
Cash dividends and dividend equivalents paid	(12.5)	(12.5)
Net cash provided by (used in) financing activities	25.0	(14.9)
Net decrease in cash, cash equivalents and restricted cash during the period	(21.2)	(41.8)
Cash, cash equivalents and restricted cash at beginning of period	71.3	317.0
Cash, cash equivalents and restricted cash at end of period	$ 50.1	$ 275.2