| In millions, except per share items | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 | Dec-31-14 |
| | 8-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | -17.4 | -27.4 | -49.4 | -20.4 | -44.8 | 3.5 | -25.4 | 15.3 |
| Depreciation and amortization [+] | 5.4 | 8.6 | 9.6 | 10.4 | 12.7 | 25.4 | 26.2 | 26.4 |
| Depreciation | 5.4 | 8.6 | 9.6 | 10.4 | 12.7 | 25.4 | 26.2 | 26.4 |
| Asset impairment charges | 22.8 | 3.3 | 17.2 | 4.4 | 7.7 | | | |
| Stock-based compensation | 1.7 | 1.1 | 1.8 | 2.8 | 2.7 | 3.1 | 2.7 | 1.1 |
| Deferred taxes | | | | | -23.2 | 1.4 | -14.1 | 8.3 |
| Change in working capital [+] | -12.7 | 18.3 | 26.2 | 10.1 | -2.5 | 0.6 | -42.1 | -39.5 |
| Accounts receivable | | 10.7 | -3.7 | 3.0 | -8.3 | 28.1 | | |
| Inventories | | | | | | | 0.9 | 1.2 |
| Accounts payable | -11.5 | 10.0 | 31.0 | 10.5 | 9.4 | -12.8 | -26.7 | -25.8 |
| Accrued expenses | | -2.4 | -1.1 | -3.4 | -3.2 | 2.2 | -5.3 | 1.3 |
| Deferred revenues | | | | | | -16.9 | | |
| Income taxes | | | | | -0.4 | | 0.6 | 0.0 |
| Other | -1.3 | | | | | | -11.7 | -16.2 |
| Other operating activities | -24.5 | -23.0 | -12.5 | -27.7 | 8.0 | -19.5 | 63.3 | 20.4 |
| Cash from operations | -24.8 | -19.0 | -7.1 | -20.4 | -39.4 | 14.6 | 10.7 | 32.1 |
| |
| Capital expenditures [+] | -1.5 | -11.2 | -3.8 | -3.5 | -4.8 | -6.8 | -6.0 | -27.7 |
| Purchases of property and equipment | -1.5 | -11.2 | -3.8 | -3.5 | -4.8 | -6.8 | -6.0 | -27.7 |
| Sales of property and equipment | 4.5 | 2.0 | 2.2 | 85.2 | 2.2 | 6.5 | 0.0 | 0.9 |
| Sales of short-term investments, net [+] | 8.0 | 11.8 | -11.2 | -8.4 | | | | |
| Purchases of short-term investments | | -58.8 | -65.3 | -9.6 | | | | |
| Sales of short-term investments | 8.0 | 70.6 | 54.1 | 1.2 | | | | |
| Other cash from investing | 26.4 | | | 9.4 | 1.5 | 3.0 | | |
| Cash from investing | 37.4 | 2.6 | -12.8 | 82.7 | -1.1 | 2.7 | -6.0 | -26.7 |
| |
| Cash dividends paid | | | | | -0.6 | -0.6 | -5.9 | -5.9 |
| Financing costs | | -0.1 | 0.0 | 0.0 | -0.2 | -0.1 | | |
| Other cash from financing | -1.2 | 9.8 | -0.9 | -0.9 | -1.2 | -0.5 | -0.1 | |
| Cash from financing | -1.2 | 9.9 | -0.8 | -0.9 | -1.7 | -0.9 | -5.9 | -5.9 |
| |
| Free cash flow | -26.3 | -30.2 | -10.9 | -23.9 | -44.2 | 7.8 | 4.7 | 4.5 |
| Per share (diluted) | ($0.47) | ($1.97) | ($0.72) | ($1.59) | ($2.98) | $0.53 | $0.32 | $0.31 |
| |
| Cash paid for interest | | 0.4 | 0.5 | 0.4 | 0.3 | 0.3 | 0.2 | 0.2 |
| Cash paid for income taxes | | -1.0 | 0.1 | 0.0 | 0.2 | 0.4 | -0.2 | 0.2 |