| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-19 | Dec-31-18 | Dec-05-18 | Dec-31-17 | Dec-05-17 | Dec-31-16 |
| | 10-K | 10-K | 10-K | 10-K | 8-K | 10-K | 8-K | 10-K |
| Net income | 148.4 | 60.6 | -553.8 | -39.8 | -45.3 | 117.8 | 117.8 | -135.6 |
| Depreciation and amortization | 24.1 | 64.3 | 275.6 | 243.6 | | 209.3 | | 208.4 |
| Asset impairment charges | | 10.7 | 625.7 | 147.9 | | | | 161.6 |
| Stock-based compensation | 6.7 | 0.9 | 12.9 | 22.9 | | 17.7 | | 13.8 |
| Deferred taxes | | | -131.0 | -10.9 | | -57.7 | | -71.2 |
| Change in working capital [+] | -16.1 | -15.0 | 21.4 | 7.7 | | -8.4 | | 34.2 |
| Accounts receivable | -10.7 | -31.0 | 33.3 | -8.0 | | -27.9 | | -11.8 |
| Inventories | | | 0.0 | 0.0 | | 2.8 | | 0.2 |
| Accounts payable | -3.2 | 23.1 | -15.6 | 28.0 | | 8.2 | | 27.4 |
| Accrued expenses | -0.3 | -3.3 | 3.1 | -5.5 | | 7.0 | | -5.1 |
| Income taxes | 0.1 | 1.2 | 0.3 | -2.0 | | 0.0 | | 20.9 |
| Other | -2.1 | -5.0 | 0.2 | -5.0 | | 1.5 | | 2.6 |
| Other operating activities | -3.7 | 54.4 | 18.6 | -18.7 | | -8.7 | | 29.0 |
| Cash from operations | 159.4 | 176.0 | 269.4 | 352.7 | | 270.1 | | 240.1 |
| |
| Capital expenditures [+] | -30.4 | -30.3 | -422.8 | -446.3 | | -255.6 | | -186.1 |
| Purchases of property and equipment | -30.4 | -30.3 | -422.8 | -446.3 | | -255.6 | | -186.1 |
| Sales of property and equipment | 69.4 | 79.5 | 31.9 | 25.9 | | 21.7 | | 74.8 |
| Acquisitions | | 13.0 | -3.7 | -30.0 | | -58.0 | | -0.6 |
| Other cash from investing | -10.1 | -26.0 | | | | -1.5 | | 0.9 |
| Cash from investing | 28.9 | 36.2 | -394.6 | -450.3 | | -293.4 | | -111.0 |
| |
| Repurchase of common stock, net | -27.4 | -52.0 | | | | 18.6 | | |
| Other cash from financing | -11.0 | -108.8 | 119.3 | 103.3 | | 4.5 | | -129.1 |
| Cash from financing | -38.5 | -160.7 | 119.3 | 103.3 | | 23.1 | | -129.1 |
| |
| Free cash flow | 129.0 | 145.7 | -153.4 | -93.5 | | 14.5 | | 54.0 |
| Per share (diluted) | $12.85 | $12.77 | ($2.90) | ($1.80) | | $0.28 | | $1.08 |
| |
| Cash paid for interest | 0.6 | 4.8 | 33.7 | 34.5 | | 33.9 | | 35.7 |
| Cash paid for income taxes | 0.2 | | 0.3 | 3.6 | | | | 0.0 |