| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 6-K | 6-K |
| Net income | -108.2 | -181.0 | -102.7 | -88.4 | -53.1 | -70.8 | -23.3 |
| Depreciation and amortization [+] | 2.7 | 2.8 | 1.4 | 1.2 | 1.3 | | |
| Depreciation | 2.7 | 2.8 | 1.4 | 0.0 | 0.0 | 0.0 | 0.0 |
| Amortization of intangible assets | | | | 1.1 | 1.3 | | |
| Asset impairment charges | 3.6 | 0.2 | | | | | |
| Stock-based compensation | 32.3 | 31.2 | 17.5 | 7.4 | 6.9 | | |
| Change in working capital [+] | -8.9 | -22.3 | 1.6 | 2.0 | -6.0 | | |
| Accounts receivable | 1.9 | -15.4 | -0.7 | -0.2 | -0.1 | | |
| Inventories | -9.1 | -5.6 | -13.9 | | | | |
| Other | -1.7 | -1.3 | 16.2 | 2.2 | -5.9 | | |
| Other operating activities | -1.2 | 11.3 | 12.4 | 14.2 | -0.7 | | |
| Cash from operations | -79.5 | -157.7 | -69.9 | -63.6 | -51.6 | | |
| |
| Capital expenditures [+] | -0.3 | -1.5 | -7.3 | -0.1 | -0.1 | | |
| Capitalized product costs | -0.3 | -1.5 | -7.3 | -0.1 | -0.1 | | |
| Purchases of intangible assets | | | | 0.0 | | | |
| Purchases of short-term investments, net | -59.7 | -84.5 | -150.8 | 7.9 | 0.0 | | |
| Purchases of short-term investments | -524.0 | -439.0 | -203.0 | | -36.1 | | |
| Sales of short-term investments | 464.3 | 354.4 | 52.1 | 7.9 | 36.1 | | |
| Other cash from investing | -0.7 | -17.8 | | | | | |
| Cash from investing | -60.6 | -103.9 | -158.2 | 7.8 | -0.1 | | |
| |
| Issuance of common stock, net | | 196.7 | 187.7 | 223.1 | | | |
| Option exercises | 2.4 | 24.0 | 6.6 | 13.7 | 0.9 | | |
| Other cash from financing | 4.9 | 48.4 | 13.3 | 34.5 | 5.0 | | |
| Cash from financing | 2.4 | 221.1 | 194.4 | 243.9 | 4.0 | | |
| |
| Free cash flow | -79.5 | -157.7 | -69.9 | -63.6 | -51.6 | | |
| Per share (diluted) | ($0.56) | ($1.23) | ($0.65) | ($0.68) | ($0.61) | | |
| |
| Cash paid for income taxes | -2.0 | -0.3 | -0.3 | -0.1 | | | |