| In millions, except per share items | Jun-30-21 | Dec-31-20 | Sep-30-20 | Sep-05-20 | Jun-30-20 | Jun-05-20 | Mar-31-20 | Dec-31-19 |
| | 10-Q | 10-K | 10-Q | 8-K | 10-Q | 8-K | 10-Q | 10-K |
| Net income | | -73.7 | -144.4 | | -129.7 | | -130.8 | -70.5 |
| Depreciation and amortization | | 55.0 | 54.7 | | 49.8 | | 49.3 | 49.0 |
| Asset impairment charges | | | | | | | 61.1 | |
| Stock-based compensation | | 3.5 | 3.3 | | 3.2 | | 2.8 | 2.8 |
| Deferred taxes | | -3.5 | -8.6 | | -8.3 | | -17.2 | -14.1 |
| Change in working capital [+] | | 26.4 | 68.2 | | 57.2 | | 50.5 | 37.9 |
| Accounts receivable | | -0.3 | 18.7 | | 42.5 | | 41.1 | 37.5 |
| Inventories | | 3.9 | 18.9 | | 6.9 | | 7.2 | 4.2 |
| Accounts payable | | 26.2 | 14.6 | | -2.3 | | 5.2 | -0.4 |
| Other | | 7.9 | 16.0 | | 10.1 | | -3.0 | -1.8 |
| Other operating activities | | 33.6 | 64.4 | | 57.7 | | 83.6 | 98.9 |
| Cash from operations | | 74.2 | 98.5 | | 91.1 | | 99.2 | 86.9 |
| |
| Capital expenditures [+] | | -33.4 | -29.2 | | -31.0 | | -35.8 | -35.9 |
| Purchases of property and equipment | | -33.4 | -29.2 | | -31.0 | | -35.8 | -35.9 |
| Sales of property and equipment | | 0.0 | 0.0 | | 0.0 | | | 0.3 |
| Other cash from investing | | 5.8 | 4.3 | | 3.4 | | 4.0 | |
| Cash from investing | | -27.6 | -24.9 | | -27.6 | | -30.9 | -32.4 |
| |
| Issuance of common stock, net | | 1.9 | 0.4 | | 0.4 | | 0.4 | 0.3 |
| Other cash from financing | | -2.0 | -3.3 | | -13.6 | | -26.8 | -52.2 |
| Cash from financing | | -0.1 | -3.0 | | -13.2 | | -26.4 | -51.9 |
| |
| Free cash flow | | 40.7 | 69.4 | | 60.0 | | 63.5 | 51.0 |
| Per share (diluted) | | $2.34 | $4.00 | | $3.46 | | $3.67 | $2.95 |
| |