| In millions, except per share items | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 |
| | 10-K | 10-K | 10-K | 10-K | 10-K |
| Net income | -114.4 | -98.6 | -43.3 | -26.8 | -9.5 |
| Depreciation and amortization [+] | 0.4 | 0.0 | | | |
| Depreciation | 0.4 | 0.0 | | | |
| Stock-based compensation | 11.8 | 13.2 | 2.8 | 1.1 | 0.2 |
| Change in working capital [+] | -0.8 | 8.8 | 4.4 | -1.8 | 0.5 |
| Other current assets | -1.3 | -4.1 | 2.4 | -2.4 | -0.5 |
| Accounts payable | -4.0 | 5.8 | 1.2 | 0.1 | 0.5 |
| Accrued expenses | 4.4 | 7.0 | 0.8 | 0.5 | 0.5 |
| Other | 0.1 | 0.1 | 0.1 | | |
| Other operating activities | 7.6 | 0.2 | 0.0 | 4.8 | 3.9 |
| Cash from operations | -95.4 | -76.3 | -36.1 | -22.6 | -4.9 |
| |
| Capital expenditures | -1.0 | -1.1 | 0.0 | 0.0 | 0.0 |
| Purchases of property and equipment | -1.0 | -1.1 | | | |
| Purchases of short-term investments, net | -30.1 | 26.3 | -46.3 | | |
| Purchases of short-term investments | -55.3 | -28.7 | -46.3 | | |
| Sales of short-term investments | 25.2 | 55.0 | | | |
| Cash from investing | -31.1 | 25.2 | -46.3 | 0.0 | 0.0 |
| |
| Issuance of common stock, net | | | 20.0 | 59.3 | 0.0 |
| Option exercises | 0.0 | 1.2 | 0.3 | 0.0 | |
| Other cash from financing | 102.4 | 115.4 | 43.2 | 0.0 | 26.7 |
| Cash from financing | 102.4 | 114.3 | 62.9 | 59.3 | 26.7 |
| |
| Free cash flow | -96.3 | -77.4 | -36.1 | -22.6 | -4.9 |
| Per share (diluted) | ($1.53) | ($1.48) | ($0.89) | ($1.01) | ($0.52) |