| In millions, except per share items | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 | Dec-31-11 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Revenue | 90.5 | 87.7 | 121.2 | 167.4 | 186.6 | 193.5 | 159.3 | 147.2 |
| Revenue growth | 3.1% | -27.7% | -27.6% | -10.3% | -3.6% | 21.5% | 8.2% | 20.8% |
| Cost of revenue | 80.5 | 82.4 | 88.3 | 116.4 | 118.1 | 118.2 | 94.2 | 90.1 |
| Gross profit (loss) | 10.0 | 5.3 | 33.0 | 51.0 | 68.4 | 75.3 | 65.1 | 57.1 |
| Gross margin | 11.1% | 6.0% | 27.2% | 30.4% | 36.7% | 38.9% | 40.8% | 38.8% |
| |
| Operating expenses: | | | | | | | | |
| Selling, general and administrative | 30.5 | 38.2 | 36.3 | 40.8 | 43.0 | 43.5 | 33.7 | 35.2 |
| Research and development | 20.0 | 16.3 | 20.9 | 24.7 | 26.3 | 22.5 | 21.7 | 22.4 |
| Restructuring and exit costs | 0.0 | 2.2 | 0.3 | 2.5 | | | | |
| Total operating expenses | 50.7 | 57.0 | 58.9 | 68.0 | 69.3 | 66.1 | 55.4 | 57.6 |
| Loss from operations | -40.7 | -51.7 | -25.9 | -17.0 | -0.9 | 9.2 | 9.7 | -0.5 |
| Operating margin | -45.0% | -58.9% | -21.4% | -10.2% | -0.5% | 4.8% | 6.1% | -0.3% |
| Interest expense | 4.5 | 1.4 | -0.2 | -0.3 | -0.2 | 0.0 | -0.1 | -0.1 |
| Other components of defined benefit plans, net | 0.1 | 0.1 | | | | | | |
| Other income | -0.2 | -0.1 | -0.1 | | | 0.1 | 0.1 | -0.1 |
| Foreign currency exchange loss, net | 0.5 | 0.2 | 0.2 | 0.4 | 0.8 | 0.6 | | |
| Loss from continuing operations before income taxes | -45.5 | -53.3 | -19.6 | -17.7 | -1.9 | 8.5 | 9.5 | 0.4 |
| Income tax provision | -1.1 | 0.6 | 4.1 | 4.6 | 4.3 | 2.2 | 2.3 | 1.9 |
| Tax rate | 2.4% | | | | | 25.3% | 24.7% | 444.0% |
| Loss from continuing operations | -44.4 | -53.9 | | | | | | |
| Income from discontinued operations, net of income taxes | 7.9 | 10.7 | | | | | | |
| Net loss | -36.5 | -43.1 | -23.7 | -22.3 | -6.3 | 6.3 | 7.2 | -1.4 |
| |
| Net income (loss) per share - basic and diluted: | | | | | | | | |
| Continuing operations | 0.0 | 0.0 | | | | | | |
| |
| Basic and diluted (in dollars per share) | ($0.89) | ($1.22) | ($0.74) | ($0.73) | ($0.21) | $0.22 | $0.25 | ($0.05) |
| |
| Weighted average common shares outstanding: | | | | | | | | |
| Weighted average common shares outstanding, basic and diluted | 41.0 | 35.5 | 31.9 | 30.7 | 29.2 | 28.9 | 28.6 | 27.6 |