| In millions, except per share items | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 | Dec-31-14 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net product revenue | | 22.3 | 59.2 | 103.3 | 173.2 | 150.2 | 173.0 | 15.0 |
| Net product revenue growth | -100.0% | -62.3% | -42.7% | -40.4% | 15.3% | -13.2% | 1055.3% | 258.3% |
| Cost of products sold | | 5.7 | 12.1 | 17.5 | 16.3 | 13.2 | 11.4 | 3.4 |
| |
| Operating expenses: | | | | | | | | |
| Research and development expenses | 17.1 | 20.4 | 32.9 | 39.3 | 33.4 | 34.6 | 25.6 | 17.3 |
| Selling, general and administrative expenses | 68.5 | 32.4 | 30.2 | 100.4 | 58.9 | 44.2 | 21.7 | 15.7 |
| Restructuring expense | | | | | 2.5 | | | |
| Total operating expense | 171.1 | 78.8 | 83.3 | 208.2 | 83.7 | 155.2 | 102.3 | 108.6 |
| Operating loss | -85.5 | 5.8 | -24.1 | -104.9 | 89.5 | -5.0 | 70.8 | -93.7 |
| Operating margin | | 26.0% | -40.7% | -101.6% | 51.7% | -3.3% | 40.9% | -625.4% |
| Investment and other income, net | 2.1 | 0.8 | 1.1 | 0.5 | 2.1 | 2.8 | 1.2 | 0.9 |
| Interest expense | | | | -10.6 | -1.1 | -1.0 | | -5.7 |
| Loss before income taxes | -93.1 | -5.1 | -38.6 | | | | | |
| Income tax provision (benefit) | -15.8 | -12.1 | -5.4 | -17.9 | 24.4 | 31.6 | 35.9 | -0.6 |
| Net loss | -77.3 | 7.0 | -33.2 | -95.3 | 68.3 | -41.3 | 41.8 | -85.5 |
| |
| Net loss per share - basic (in dollars per share) | ($1.32) | $0.13 | ($0.89) | ($2.55) | $1.69 | ($1.00) | $1.03 | ($2.36) |
| Net loss per share - diluted (in dollars per share) | ($1.32) | $0.13 | ($0.89) | ($2.55) | $1.63 | ($1.00) | $0.96 | ($2.36) |
| |
| Weighted average number of shares outstanding - basic (in shares) | 58.5 | 53.0 | 37.4 | 37.3 | 40.5 | 41.2 | 40.6 | 36.2 |
| Weighted average number of shares outstanding - diluted (in shares) | 58.5 | 54.9 | 37.4 | 37.3 | 41.8 | 41.2 | 43.6 | 36.2 |