| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 |
| | 10-K | 10-K | 10-K/A | 10-K | S-1/A |
| Net income | -108.9 | -101.3 | -68.8 | -51.1 | -26.3 |
| Depreciation and amortization | 3.3 | 3.2 | 1.3 | 0.7 | 0.4 |
| Stock-based compensation | 14.3 | 8.4 | 3.0 | 1.7 | 0.7 |
| Change in working capital [+] | 2.7 | 1.0 | -1.0 | 2.4 | 2.5 |
| Other current assets | -0.3 | -1.8 | -4.7 | -1.0 | |
| Accounts payable | 1.6 | 0.1 | 0.5 | 1.2 | 1.3 |
| Accrued expenses | 1.4 | 2.7 | 3.2 | 2.1 | |
| Other | | | | | 1.2 |
| Other operating activities | 282.1 | 38.5 | 34.2 | 0.0 | 0.1 |
| Cash from operations | 193.6 | -50.3 | -31.3 | -46.3 | -22.6 |
| |
| Capital expenditures [+] | -1.2 | -3.3 | -16.2 | -1.0 | -1.5 |
| Purchases of property and equipment | -1.2 | -3.3 | -16.2 | -1.0 | -1.5 |
| Sales of property and equipment | | | 0.3 | 0.0 | |
| Purchases of short-term investments, net | -243.1 | 39.5 | -93.0 | | |
| Purchases of short-term investments | -409.3 | -100.0 | -93.0 | | |
| Sales of short-term investments | 166.2 | 139.5 | | | |
| Cash from investing | -244.3 | 36.2 | -108.9 | -1.0 | -1.5 |
| |
| Issuance of common stock, net | | 42.2 | 122.1 | | |
| Option exercises | 1.8 | 1.4 | 1.2 | 0.7 | |
| Other cash from financing | 3.5 | -18.4 | 96.6 | 24.7 | 51.8 |
| Cash from financing | 1.8 | 22.4 | 217.5 | 24.0 | 51.8 |
| |
| Free cash flow | 192.4 | -53.6 | -47.5 | -47.3 | -24.2 |
| Per share (diluted) | $4.63 | ($1.44) | ($4.30) | ($11.28) | ($8.21) |
| |
| Cash paid for interest | | 1.7 | 0.7 | 0.4 | |