| 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 | 20-F | 20-F | 10-K | 10-K | 10-K | 20-F |
| Net income | -192.8 | -17.8 | -5.8 | -4.3 | -26.2 | -26.2 | -68.5 | -47.2 |
| Depreciation and amortization | 28.3 | 5.7 | 1.0 | 1.0 | 3.9 | 6.1 | 6.2 | 7.5 |
| Asset impairment charges | 89.1 | 0.8 | 0.3 | 0.1 | | 2.5 | 34.4 | 10.7 |
| Stock-based compensation | 8.5 | 0.4 | 0.0 | 0.6 | 1.6 | 7.8 | 9.1 | 7.2 |
| Deferred taxes | | | | | | -2.1 | 0.3 | -1.6 |
| Change in working capital [+] | 43.9 | 8.9 | 4.8 | 15.0 | 8.4 | 8.2 | -35.0 | 10.1 |
| Accounts receivable | 0.0 | 0.1 | 0.1 | 0.8 | 2.9 | 1.4 | -1.2 | -1.5 |
| Inventories | | | 0.2 | 0.5 | 0.6 | 2.0 | 1.3 | 0.0 |
| Deferred revenues | -0.1 | -0.6 | -0.6 | -0.1 | -1.2 | -0.8 | -1.3 | -1.9 |
| Other | 43.9 | 9.4 | 5.1 | 13.9 | 6.1 | 5.6 | -33.8 | 13.5 |
| Other operating activities | -7.7 | -26.5 | -2.9 | -14.3 | 4.7 | -5.3 | 36.0 | -9.7 |
| Cash from operations | -30.8 | -28.5 | -2.6 | -1.8 | -7.6 | -9.0 | -17.5 | -23.2 |
| |
| Capital expenditures [+] | -17.6 | -102.2 | 0.0 | 0.0 | -0.1 | -0.1 | -0.2 | -0.5 |
| Purchases of property and equipment | -17.6 | -102.2 | | | -0.1 | -0.1 | -0.2 | -0.4 |
| Capitalized product costs | | | | | | | | -0.1 |
| Purchases of intangible assets | -0.3 | | | | | | | -0.1 |
| Acquisitions | | | | | | -1.1 | | |
| Other cash from investing | -4.1 | -20.5 | -2.0 | | 1.0 | | | |
| Cash from investing | -22.0 | -122.7 | -2.0 | 0.0 | 0.9 | -1.2 | -0.2 | -0.6 |
| |
| Issuance of common stock, net | | | 0.4 | 0.7 | 2.3 | 10.9 | 5.8 | 16.8 |
| Option exercises | | 0.3 | 0.1 | | | | | 0.2 |
| Other cash from financing | | 205.4 | 4.6 | 0.9 | 0.1 | -1.3 | 8.3 | 11.7 |
| Cash from financing | 0.0 | 205.1 | 4.9 | 1.6 | 2.4 | 9.5 | 14.1 | 28.3 |
| |
| Free cash flow | -48.4 | -130.8 | -2.6 | -1.8 | -7.7 | -9.1 | -17.7 | -23.6 |
| Per share (diluted) | ($0.73) | ($4.24) | ($0.44) | ($0.67) | ($4.63) | ($14.61) | ($8.90) | ($0.62) |