| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | -22.0 | -49.7 | -72.8 | -20.7 | -36.4 | -39.7 | -135.4 | -144.7 |
| Depreciation and amortization | 78.2 | 78.2 | 80.5 | 76.7 | 70.5 | 69.1 | 72.1 | 81.8 |
| Asset impairment charges | 0.1 | | 20.8 | 3.2 | 0.7 | | 102.6 | 151.2 |
| Stock-based compensation | 1.3 | 2.0 | 1.4 | 1.1 | 0.6 | 1.2 | 3.0 | 2.2 |
| Deferred taxes | 0.4 | -0.6 | 0.2 | 0.1 | -0.2 | 0.8 | 0.0 | -0.6 |
| Change in working capital [+] | -21.8 | -12.0 | -12.6 | 4.2 | -15.9 | -26.5 | 39.5 | 10.3 |
| Accounts receivable | -12.3 | -6.4 | 18.9 | -2.1 | -19.3 | -2.7 | 11.2 | 19.7 |
| Inventories | -17.6 | -7.8 | 13.2 | -0.3 | -23.5 | -10.8 | 10.5 | 64.9 |
| Other | 8.1 | 2.2 | -44.8 | 6.6 | 26.9 | -13.0 | 17.7 | -74.3 |
| Other operating activities | -0.7 | 9.2 | 3.2 | 3.1 | 10.8 | 34.1 | -20.4 | 1.7 |
| Cash from operations | 35.5 | 27.2 | 20.8 | 67.7 | 30.1 | 39.1 | 61.4 | 101.9 |
| |
| Capital expenditures [+] | -52.1 | -43.4 | -13.7 | -75.8 | -104.0 | -28.0 | -10.7 | -95.3 |
| Purchases of property and equipment | -52.1 | -43.4 | -13.7 | -75.8 | -104.0 | -28.0 | -10.7 | -95.3 |
| Sales of property and equipment | 8.1 | 1.3 | 19.4 | 11.0 | 0.5 | 2.8 | | |
| Other cash from investing | | 1.6 | -0.5 | 0.6 | 0.0 | 2.4 | 0.0 | -0.1 |
| Cash from investing | -43.9 | -40.5 | 5.2 | -64.2 | -103.5 | -22.8 | -10.7 | -95.3 |
| |
| Cash dividends paid | | -8.2 | -1.9 | -1.9 | -31.3 | | | |
| Other cash from financing | 10.3 | 11.6 | -9.8 | -15.1 | 113.0 | -29.3 | -39.9 | -28.4 |
| Cash from financing | 10.3 | 3.4 | -11.7 | -17.0 | 81.7 | -29.3 | -39.9 | -28.4 |
| |
| Free cash flow | -16.5 | -16.2 | 7.1 | -8.1 | -73.9 | 11.1 | 50.8 | 6.6 |
| Per share (diluted) | ($0.12) | ($0.27) | $0.15 | ($0.17) | ($1.78) | $0.32 | $1.53 | $0.20 |
| |
| Cash paid for interest | 47.3 | 49.2 | 49.8 | 47.8 | 38.6 | 31.7 | 32.9 | 33.0 |
| Cash paid for income taxes | 6.6 | 4.3 | 2.7 | 3.1 | 2.1 | 3.0 | 1.3 | 0.6 |