| 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 |
| | 8-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | 32.5 | -33.4 | -57.9 | -5.9 | -5.7 | -3.3 | -0.2 | 5.4 |
| Depreciation and amortization | | 19.9 | 19.9 | 21.6 | 20.9 | 17.0 | 15.0 | 13.6 |
| Depreciation | 18.7 | | | | | | | |
| Asset impairment charges | | 12.2 | | | | | | 0.5 |
| Stock-based compensation | | 0.7 | 0.8 | 0.4 | 0.4 | 0.3 | 0.2 | 0.3 |
| Deferred taxes | | | 5.4 | -0.3 | 0.3 | 1.5 | -1.6 | -1.8 |
| Change in working capital [+] | | -0.3 | 15.7 | 0.6 | 2.0 | -3.4 | -0.2 | -3.1 |
| Restricted cash | | | | | | | | 0.6 |
| Accounts receivable | | -2.6 | 3.0 | 2.0 | -0.9 | -1.5 | -0.1 | -2.0 |
| Other current assets | | 0.7 | -2.2 | -0.2 | 1.6 | -2.8 | -0.3 | -0.6 |
| Other | | 1.6 | 14.9 | -1.2 | 1.3 | 0.9 | 0.2 | -1.0 |
| Other operating activities | | 3.2 | 4.9 | 6.0 | 8.3 | 3.8 | 4.7 | -3.5 |
| Cash from operations | | 2.3 | -11.3 | 22.5 | 26.2 | 15.8 | 18.0 | 11.4 |
| |
| Capital expenditures [+] | | -3.2 | -4.0 | -12.7 | -22.1 | -23.2 | -14.9 | -20.1 |
| Purchases of property and equipment | | -3.2 | -4.0 | -12.7 | -22.1 | -23.2 | -14.9 | -20.1 |
| Sales of property and equipment | | 0.2 | 0.1 | 0.0 | 0.0 | 5.5 | 0.2 | 2.4 |
| Acquisitions | | | | -6.3 | -79.7 | -4.0 | | -25.5 |
| Other cash from investing | | 0.6 | 0.2 | 0.3 | 0.9 | 2.3 | | 2.1 |
| Cash from investing | | -2.4 | -3.8 | -18.7 | -100.9 | -19.3 | -14.7 | -41.1 |
| |
| Cash dividends paid | | | | | | | -5.9 | -4.1 |
| Issuance of common stock, net | | | | | 0.6 | -3.7 | -2.1 | 23.3 |
| Financing costs | | 0.0 | -1.6 | -0.1 | -3.8 | -0.8 | -1.8 | -1.4 |
| Other cash from financing | | -9.7 | 20.8 | -13.7 | 74.8 | 3.4 | 21.9 | 4.1 |
| Cash from financing | | -9.7 | 22.4 | -13.6 | 79.2 | 0.5 | 15.8 | 24.6 |
| |
| Free cash flow | | -0.9 | -15.3 | 9.8 | 4.1 | -7.3 | 3.1 | -8.8 |
| Per share (diluted) | | ($0.06) | ($1.07) | $0.72 | $0.30 | ($0.53) | $0.21 | ($0.70) |
| |
| Cash paid for interest | | 19.9 | 9.5 | 19.3 | 18.3 | 15.3 | 16.9 | 15.4 |
| Cash paid for income taxes | | 0.0 | 0.0 | -0.1 | 0.2 | 0.2 | | |