| In millions, except per share items | Jun-30-23 | Mar-31-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 |
| | 10-Q | 8-K | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
| Net Cash Provided by (Used in) Operating Activities [Abstract] | | | | | | | | |
| Net Income (Loss) Attributable to Noncontrolling Interest | -38.8 | -33.0 | -26.1 | -13.6 | -14.8 | -11.6 | -13.2 | -100.1 |
| |
| Adjustments to reconcile net loss to net cash from (used in) operating activities: | | | | | | | | |
| Depreciation and amortization | 47.5 | 47.3 | 47.2 | 45.3 | 45.7 | 46.1 | 46.2 | 46.4 |
| Amortization of debt issuance costs and discount | 1.6 | | 1.4 | 1.4 | 1.3 | 1.3 | 1.4 | 11.8 |
| Impairments of property, plant and equipment | | | | | | | | |
| Loss on extinguishment of debt and write-off of debt issuance costs | | | | | | | | |
| Share of net income from joint venture, net of cash dividends received | -3.2 | -2.6 | -0.3 | -0.5 | -2.1 | -2.9 | -6.3 | -5.3 |
| Share-based compensation expense | 1.7 | | 4.4 | 4.5 | 5.1 | 3.3 | 3.2 | 3.2 |
| Deferred income taxes | -1.8 | -1.3 | -1.8 | -3.0 | -1.7 | -3.3 | -4.8 | 36.5 |
| Other | -1.2 | -2.7 | -3.2 | -3.9 | -4.2 | -2.4 | -2.6 | -5.0 |
| Changes in operating assets and liabilities: | | | | | | | | |
| Accounts receivable | 3.3 | 7.2 | -4.9 | -2.1 | -2.3 | 2.7 | 13.7 | 6.1 |
| Inventories | 7.8 | -1.6 | -6.7 | -11.0 | -11.5 | -12.9 | -13.0 | -12.3 |
| Accounts payable | 3.6 | 0.0 | 8.6 | 2.2 | 2.9 | 4.7 | 0.3 | 1.1 |
| Income taxes receivable and payable, net | -1.7 | | -1.5 | 0.3 | 1.3 | -4.8 | -4.5 | 4.9 |
| Other | -4.3 | | -4.1 | -3.8 | -1.0 | -7.6 | -2.8 | -6.3 |
| Net cash provided by (used in) operating activities | 18.9 | 13.2 | 7.7 | 7.2 | 7.1 | 2.5 | 15.6 | 1.9 |
| |
| Cash flows from investing activities | | | | | | | | |
| Acquisition of property, plant and equipment | -20.4 | | -18.0 | -17.7 | -16.9 | -17.0 | -18.2 | -17.8 |
| Proceeds from sale of property, plant, and equipment | 2.8 | | | 0.7 | 1.8 | 1.4 | 1.4 | 1.3 |
| |
| Cash paid for post-closing adjustments on sale of business | | | | | | | | |
| Cash settlements of interest rate swap | | | | | | | | |
| Other | | | | | | | | |
| Net cash used in investing activities | -17.6 | -17.2 | -17.5 | -17.0 | -15.1 | -19.5 | -36.1 | 704.0 |
| |
| Cash flows from financing activities | | | | | | | | |
| Proceeds from long-term debt | 61.0 | | 46.0 | 37.0 | 35.0 | 29.0 | 171.0 | 167.5 |
| Repayments of long-term debt | -63.2 | | -48.0 | -33.8 | -35.8 | -31.7 | -93.7 | -847.3 |
| |
| Proceeds from issuance of preferred stock | | | | | | | | |
| Redemption of preferred stock | | | | | | | | |
| Dividends paid | | | | | | | | |
| Cash paid for debt issuance costs | -0.1 | | 0.0 | 7.2 | | | 0.0 | -6.7 |
| Proceeds from short-term debt, net | 3.6 | 2.9 | | | | | | -1.6 |
| Other | -3.2 | | -3.1 | -3.6 | -4.0 | -4.7 | -5.2 | -4.9 |
| Net cash provided by (used in) financing activities | -1.9 | -2.4 | -5.2 | -0.5 | -5.4 | -8.6 | 2.6 | -754.3 |