| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-05-19 | Dec-31-18 | Dec-05-18 | Dec-31-17 |
| | 10-K | 10-K | 10-K | 10-K | 8-K | 10-K | 8-K | 10-K |
| Revenues: | | | | | | | | |
| Revenues | 151.9 | 77.4 | 104.9 | 64.2 | 64.2 | 60.1 | 60.1 | 157.7 |
| Revenues growth | 96.2% | -26.2% | 63.4% | 6.8% | 6.8% | -61.9% | -61.9% | 71.7% |
| Costs and expenses: | | | | | | | | |
| Cost of product sales | 3.4 | 2.7 | | | | | | |
| Cost of manufacturing services | 4.0 | | | | | | | |
| Research and development | 207.0 | 214.6 | 193.2 | 195.3 | | 190.8 | | 147.2 |
| Selling, general and administrative | 58.9 | 63.0 | 42.7 | 46.1 | 46.1 | 40.5 | 40.5 | 32.7 |
| Total costs and expenses | 273.4 | 280.2 | 235.9 | 241.4 | 241.4 | 231.3 | 231.3 | 179.9 |
| Loss from operations | -121.4 | -202.8 | -131.1 | -177.2 | -177.2 | -171.2 | -171.2 | -22.1 |
| Operating margin | -79.9% | -261.9% | -125.0% | -276.0% | -276.0% | -284.8% | -284.8% | -14.0% |
| Net loss | -119.8 | -202.1 | -129.7 | -151.8 | -151.8 | -171.5 | -171.5 | -19.6 |
| |
| Other comprehensive income (loss): | | | | | | | | |
| Comprehensive income (loss) | -119.7 | -202.2 | -129.8 | -151.8 | -151.8 | -171.4 | -171.4 | -19.6 |
| |
| Net income (loss) per common share: | | | | | | | | |
| Basic net loss per common share (in usd per share) | ($1.95) | ($3.37) | ($2.47) | | ($3.16) | | ($4.19) | |
| Diluted net loss per common share (in usd per share) | ($1.95) | ($3.37) | ($2.47) | | ($3.16) | | ($4.19) | |
| |
| Weighted average common shares outstanding: | | | | | | | | |
| Basic weighted average common shares outstanding (in shares) | 61.4 | 59.9 | 52.4 | 48.1 | 48.1 | 40.9 | 40.9 | 36.1 |
| Diluted weighted average common shares outstanding (in shares) | 61.4 | 59.9 | 52.4 | 48.1 | 48.1 | 40.9 | 40.9 | 36.1 |