| In millions, except per share items | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 | Dec-31-11 | Dec-31-10 | Dec-31-09 | Dec-31-08 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | -38.1 | -39.8 | -24.0 | -12.1 | -4.3 | -2.4 | -1.3 | -4.0 |
| Depreciation and amortization [+] | 3.0 | 3.1 | 2.8 | 3.3 | 2.6 | 2.6 | | 2.9 |
| Depreciation | | | | 1.0 | 1.0 | 0.9 | | 1.4 |
| Amortization of intangible assets | 3.0 | 3.1 | 2.8 | 2.3 | 1.6 | 1.7 | | 1.4 |
| Stock-based compensation | 4.8 | 5.6 | 5.3 | 2.2 | 1.6 | 0.7 | | |
| Deferred taxes | -2.7 | 0.0 | 0.1 | -2.5 | 0.1 | 0.2 | 0.1 | 0.0 |
| Change in working capital [+] | -0.1 | 12.0 | 1.5 | -3.4 | -1.0 | -2.2 | -0.3 | -5.3 |
| Accounts receivable | 0.3 | -1.4 | -0.3 | -0.3 | -0.8 | -2.1 | -0.2 | -0.5 |
| Inventories | -9.1 | 2.6 | -3.0 | -3.3 | -0.3 | -1.1 | 1.0 | -3.6 |
| Other current assets | 1.8 | 0.2 | -0.7 | -0.8 | -0.4 | -0.1 | | |
| Accounts payable | -1.6 | 0.7 | 0.6 | -0.4 | 0.2 | 0.4 | -0.4 | -0.2 |
| Accrued expenses | 4.6 | 1.6 | 0.9 | 1.4 | 0.2 | 0.8 | | |
| Other | 3.9 | 8.3 | 4.0 | | | | | |
| Other operating activities | -2.3 | -7.0 | -3.1 | 0.5 | 1.3 | 1.0 | 4.1 | 1.6 |
| Cash from operations | -35.4 | -26.0 | -17.2 | -11.9 | 0.2 | -0.3 | 2.7 | -4.7 |
| |
| Capital expenditures [+] | -1.8 | -1.7 | -0.7 | -0.8 | -1.0 | -0.6 | 0.0 | 0.0 |
| Purchases of property and equipment | -1.8 | -1.7 | -0.7 | -0.8 | -1.0 | -0.6 | | |
| Sales of property and equipment | | | | 0.0 | | | | |
| Purchases of intangible assets | | -1.1 | -0.4 | -2.3 | -1.0 | -2.3 | | |
| Acquisitions | | | | -14.4 | | | | |
| Purchases of short-term investments, net | 31.0 | -41.0 | -19.2 | 1.2 | -5.5 | | | |
| Purchases of short-term investments | -55.0 | -91.5 | -33.7 | -6.5 | -5.5 | | | |
| Sales of short-term investments | 86.0 | 50.5 | 14.5 | 7.7 | | | | |
| Cash from investing | 29.2 | -43.9 | -20.3 | -16.2 | -7.5 | -2.9 | -0.2 | 0.6 |
| |
| Issuance of common stock, net | | 80.6 | | 51.5 | 27.0 | 4.5 | 0.0 | 5.7 |
| Option exercises | 2.0 | 2.3 | 2.8 | 1.2 | | | | |
| Other cash from financing | 3.8 | 4.2 | 5.4 | 2.4 | | | | |
| Cash from financing | 1.8 | 82.6 | 2.6 | 52.6 | 23.9 | 3.2 | -2.8 | 4.4 |
| |
| Free cash flow | -37.2 | -27.7 | -17.9 | -12.7 | -0.7 | -0.9 | 2.7 | -4.7 |
| Per share (diluted) | ($1.45) | ($1.13) | ($1.05) | ($1.02) | ($0.08) | ($0.15) | $0.53 | ($0.98) |
| |
| Cash paid for interest | 0.0 | 0.0 | 0.0 | 0.0 | 0.2 | 0.5 | | |
| Cash paid for income taxes | 0.0 | 0.1 | | | 0.3 | 0.1 | | |