| In millions, except per share items | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 |
| | 10-K | 10-K | 10-K | 10-K | S-1 |
| Net sales | 20.2 | 1.6 | | 0.0 | 0.1 |
| Net sales growth | 1138.8% | | -100.0% | -69.8% | |
| Grant and other income | 0.3 | 1.1 | 2.4 | | |
| Cost of goods sold | 9.3 | 1.6 | | | |
| Gross profit | 11.1 | 1.1 | 2.4 | 1.6 | 1.1 |
| Gross margin | 55.1% | 68.8% | | 9700.0% | 2013.2% |
| |
| Operating expenses: | | | | | |
| Research and development | 20.9 | 60.4 | 40.7 | 20.2 | 10.2 |
| Selling, general and administrative | 73.7 | 63.1 | 21.1 | 8.0 | |
| Total operating expenses | 94.7 | 123.5 | 61.8 | 28.2 | 14.3 |
| Loss from operations | -83.5 | -122.4 | -59.3 | -26.6 | -13.2 |
| Operating margin | -414.5% | -7521.8% | | -166431.3% | -24964.2% |
| |
| Other income (expense): | | | | | |
| Interest and other income | 3.0 | 2.8 | 1.6 | 0.1 | 0.0 |
| Interest expense | -10.7 | -7.2 | -2.5 | 0.0 | 0.0 |
| Change in fair value of warrants | 0.0 | 0.7 | 0.2 | 0.0 | 0.0 |
| Total other income (expense) | -7.7 | -3.7 | -0.7 | 0.1 | 0.0 |
| Net loss before benefit from income taxes | -91.3 | -126.0 | -60.1 | | |
| Benefit from income taxes | 0.1 | 0.5 | | | |
| Net loss | -91.1 | -125.6 | -60.1 | -26.6 | -13.2 |
| |
| Other comprehensive income (loss), net of tax: | | | | | |
| Unrealized gains (losses) on investments | 0.0 | 0.1 | | | |
| Foreign currency translation adjustments | 0.0 | 0.0 | | | |
| |
| Net loss per common share - basic and diluted | ($2.14) | ($4.81) | ($4.99) | ($13.09) | ($7.17) |
| |
| Weighted average common shares outstanding - basic and diluted | 42.6 | 26.1 | 12.0 | 2.0 | 1.8 |