| 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/A | S-1/A |
| Net income | -42.9 | -50.0 | -55.2 | -23.2 | 0.0 |
| Depreciation and amortization | 0.1 | 0.1 | 0.0 | 0.0 | 0.0 |
| Stock-based compensation | 7.3 | 4.9 | 1.2 | 0.6 | 0.2 |
| Change in working capital [+] | 1.8 | -5.7 | 3.0 | 1.6 | -0.4 |
| Accounts receivable | | | | | -0.1 |
| Income taxes | | | -0.1 | 0.1 | |
| Other | 1.8 | -5.7 | 3.1 | 1.6 | -0.3 |
| Other operating activities | 0.5 | -0.1 | -0.2 | -0.1 | -7.9 |
| Cash from operations | -33.2 | -50.7 | -51.2 | -21.0 | -8.1 |
| |
| Capital expenditures | 0.0 | 0.0 | -0.4 | 0.0 | 0.0 |
| Purchases of property and equipment | | | -0.4 | 0.0 | 0.0 |
| Acquisitions | | | | | -16.0 |
| Sales of short-term investments, net [+] | 70.0 | -70.0 | 0.0 | 16.0 | 0.0 |
| Purchases of short-term investments | -15.0 | -90.0 | -35.0 | -3.0 | |
| Sales of short-term investments | 85.0 | 20.0 | 35.0 | 19.0 | 0.0 |
| Cash from investing | 70.0 | -70.0 | -0.4 | 16.0 | -16.0 |
| |
| Issuance of common stock, net | | 24.9 | 85.4 | | |
| Option exercises | 0.1 | 0.3 | 0.0 | 0.5 | |
| Other cash from financing | 5.2 | 48.6 | 0.1 | 80.6 | 30.7 |
| Cash from financing | 5.1 | 73.2 | 85.4 | 80.1 | 30.7 |
| |
| Free cash flow | -33.2 | -50.7 | -51.6 | -21.1 | -8.1 |
| Per share (diluted) | ($0.79) | ($1.73) | ($3.27) | ($65.95) | |