| 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 | -14.4 | -10.2 | -12.0 | -2.2 | -8.6 | -3.3 | 0.5 | -3.4 |
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| Adjustments to reconcile net loss to net cash from (used in) operating activities: | | | | | | | | |
| Depreciation and amortization | 11.6 | 11.5 | 13.3 | 11.2 | 11.3 | 11.4 | 11.3 | 11.6 |
| Amortization of debt issuance costs and discount | 0.9 | | 0.3 | 0.4 | 0.3 | 0.3 | 0.3 | 0.3 |
| 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 | -1.1 | -0.3 | -2.7 | 0.8 | -0.4 | 1.9 | -2.8 | -0.8 |
| Share-based compensation expense | 0.9 | | 0.5 | 0.3 | 2.6 | 0.9 | 0.6 | 0.9 |
| Deferred income taxes | -0.4 | 0.5 | 0.0 | -1.9 | 0.1 | 0.0 | -1.1 | -0.7 |
| Other | -0.4 | -0.3 | -0.1 | -0.3 | -1.9 | -0.8 | -0.8 | -0.7 |
| Changes in operating assets and liabilities: | | | | | | | | |
| Accounts receivable | 0.4 | -5.5 | 10.7 | -2.4 | 4.4 | -17.6 | 13.6 | -2.5 |
| Inventories | 4.4 | -0.4 | 4.6 | -0.7 | -5.1 | -5.5 | 0.3 | -1.2 |
| Accounts payable | 4.1 | 2.8 | -1.2 | -2.1 | 0.5 | 11.4 | -7.6 | -1.5 |
| Income taxes receivable and payable, net | -0.7 | | -1.1 | 0.1 | 0.2 | -0.6 | 0.7 | 1.2 |
| Other | -1.1 | | -1.7 | -1.5 | 0.1 | -1.0 | -1.4 | 1.4 |
| Net cash provided by (used in) operating activities | 8.4 | 0.2 | 10.4 | -0.1 | 2.7 | -5.2 | 9.9 | -0.2 |
| |
| Cash flows from investing activities | | | | | | | | |
| Acquisition of property, plant and equipment | -12.2 | | -3.9 | -4.3 | -5.4 | -4.3 | -3.7 | -3.5 |
| Proceeds from sale of property, plant, and equipment | 2.8 | | | 0.0 | 0.4 | 0.0 | 0.2 | 1.1 |
| |
| Cash paid for post-closing adjustments on sale of business | | | | | | | | |
| Cash settlements of interest rate swap | | | | | | | | |
| Other | | | | | | | | |
| Net cash used in investing activities | -5.5 | -4.0 | -3.9 | -4.3 | -5.1 | -4.2 | -3.4 | -2.4 |
| |
| Cash flows from financing activities | | | | | | | | |
| Proceeds from long-term debt | 35.0 | | 14.0 | 12.0 | 12.0 | 8.0 | 5.0 | 10.0 |
| Repayments of long-term debt | -34.7 | | -19.8 | -8.7 | -10.8 | -8.7 | -5.7 | -10.6 |
| |
| Proceeds from issuance of preferred stock | | | | | | | | |
| Redemption of preferred stock | | | | | | | | |
| Dividends paid | | | | | | | | |
| Cash paid for debt issuance costs | -0.1 | | 0.1 | -0.1 | | | 7.4 | -0.4 |
| Proceeds from short-term debt, net | 0.7 | 2.9 | | | | | | -0.2 |
| Other | -1.6 | | -0.8 | -0.7 | -0.7 | -0.8 | -1.3 | -1.2 |
| Net cash provided by (used in) financing activities | 1.0 | 1.3 | -6.6 | 2.5 | 0.5 | -1.5 | -2.0 | -2.4 |