| 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 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | -22.2 | -44.2 | -10.8 | -1.5 | -15.3 | 14.0 | 80.2 | 20.7 |
| Depreciation and amortization | 10.4 | 9.1 | 9.2 | 10.8 | 11.6 | 13.0 | 14.0 | 16.7 |
| Asset impairment charges | 15.7 | 25.0 | 8.8 | | | | | |
| Stock-based compensation | 7.2 | 5.5 | 3.6 | 5.0 | 3.7 | 0.9 | 1.9 | 3.8 |
| Deferred taxes | -5.5 | 0.4 | -3.3 | -1.7 | 25.4 | 6.9 | -55.0 | 4.7 |
| Change in working capital [+] | 5.8 | 26.0 | 3.4 | -3.3 | -12.7 | -0.6 | -63.9 | -10.8 |
| Accounts receivable | 1.8 | -1.6 | 1.0 | -0.9 | -9.6 | -1.8 | 1.0 | -8.0 |
| Other current assets | 2.6 | 1.4 | 1.7 | -0.6 | 0.2 | | | |
| Deferred revenues | | | | | | | 2.8 | 1.1 |
| Other | 1.4 | 26.1 | 0.7 | -1.7 | -3.3 | 1.2 | -67.7 | -3.9 |
| Other operating activities | -3.5 | 4.4 | 0.6 | 1.1 | 2.8 | 3.4 | 64.6 | 6.4 |
| Cash from operations | 8.0 | 26.2 | 11.7 | 10.3 | 15.5 | 37.6 | 41.8 | 41.6 |
| |
| Capital expenditures [+] | -15.2 | -14.7 | -4.8 | -5.9 | -9.2 | -6.3 | -5.6 | -7.6 |
| Purchases of property and equipment | -4.4 | -3.5 | -4.8 | -5.9 | -9.2 | -6.3 | -5.6 | -7.6 |
| Capitalized product costs | -10.8 | -11.3 | | | | | | |
| Purchases of short-term investments, net | 15.0 | 0.1 | -25.4 | 0.1 | 0.0 | -2.0 | | |
| Purchases of short-term investments | -45.0 | -59.9 | -59.4 | -3.9 | -4.0 | -4.0 | | |
| Sales of short-term investments | 60.0 | 60.0 | 34.0 | 4.0 | 4.0 | 2.0 | | |
| Cash from investing | -0.2 | -14.6 | -30.2 | -5.8 | -9.2 | -8.2 | -5.6 | -7.6 |
| |
| Cash dividends paid | -10.0 | -9.8 | -9.8 | -10.1 | -15.2 | -10.3 | -14.0 | -10.8 |
| Repurchase of common stock, net | | | -6.6 | -13.5 | -10.0 | -6.5 | -15.0 | -4.3 |
| Option exercises | 0.1 | 0.3 | 0.3 | 0.2 | 0.3 | 0.1 | | |
| Other cash from financing | -1.6 | -0.3 | -0.5 | -0.5 | 0.5 | 0.1 | -3.8 | |
| Cash from financing | -11.8 | -10.4 | -17.2 | -24.3 | -25.0 | -16.7 | -32.8 | -15.2 |
| |
| Free cash flow | 3.6 | 22.7 | 6.9 | 4.4 | 6.3 | 31.3 | 36.3 | 33.9 |
| Per share (diluted) | ($0.37) | $0.60 | $0.36 | $0.22 | $0.31 | $1.52 | $1.69 | $1.57 |
| |
| Cash paid for income taxes | -0.1 | 0.0 | 0.9 | 1.1 | 2.6 | 0.7 | 1.5 | 1.4 |