| In millions, except per share items | Dec-31-16 | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 | Dec-31-11 | Dec-31-10 | Dec-31-09 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | 9.2 | 9.3 | 3.0 | 0.0 | -17.7 | -10.6 | -26.1 | -34.9 |
| Depreciation and amortization | 0.6 | 0.6 | 0.6 | 0.5 | 0.4 | 0.5 | 0.7 | 0.9 |
| Stock-based compensation | 0.1 | 0.1 | 0.0 | 0.0 | 0.0 | 0.1 | 0.0 | 0.2 |
| Deferred taxes | -2.0 | -5.2 | | | | | | -0.2 |
| Change in working capital | -4.2 | -7.8 | 3.1 | -4.3 | 13.5 | 5.4 | 6.1 | 4.0 |
| Other | -4.2 | -7.8 | 3.1 | -4.3 | 13.5 | 5.4 | 6.1 | 4.0 |
| Cash from operations | 8.4 | 6.8 | 9.2 | 2.2 | 26.9 | 19.8 | 38.7 | 7.8 |
| |
| Capital expenditures | -2.0 | -0.5 | -1.5 | -0.4 | -0.3 | -0.1 | -0.1 | -0.3 |
| Purchases of property and equipment | -2.0 | -0.5 | -1.5 | -0.4 | -0.3 | -0.1 | -0.1 | -0.3 |
| Purchases of short-term investments, net | 52.8 | 23.4 | 64.2 | 26.0 | -28.9 | -96.0 | 7.2 | -214.1 |
| Purchases of short-term investments | -45.9 | -59.2 | -49.4 | -99.7 | -205.3 | -209.0 | -174.2 | -398.3 |
| Sales of short-term investments | 98.7 | 82.6 | 113.6 | 125.7 | 176.4 | 113.0 | 181.3 | 184.2 |
| Cash from investing | -47.5 | -57.7 | 13.1 | 12.2 | 38.1 | 77.9 | 245.5 | -85.3 |
| |
| Cash dividends paid | | | | | | | | -0.4 |
| Issuance of common stock, net | | | 20.0 | | | | | |
| Other cash from financing | 34.9 | 45.5 | -28.3 | -26.4 | -60.7 | -124.9 | -290.7 | 121.9 |
| Cash from financing | 34.9 | 45.5 | -8.3 | -26.4 | -60.7 | -124.9 | -290.7 | 121.5 |
| |
| Free cash flow | 6.3 | 6.3 | 7.7 | 1.8 | 26.6 | 19.6 | 38.6 | 7.5 |
| Per share (diluted) | $0.21 | $0.21 | $0.37 | $0.13 | $2.01 | $1.48 | $2.91 | $0.57 |