| 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 | Dec-31-15 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 20-F | 20-F | 20-F |
| Net income | -443.3 | -704.5 | -268.9 | -195.1 | -139.1 | -50.4 | -37.5 | -18.0 |
| Depreciation and amortization [+] | 8.2 | 6.5 | 4.6 | 3.8 | 1.7 | 0.5 | 0.2 | 0.1 |
| Depreciation | 8.2 | 6.5 | 4.6 | 3.8 | 1.7 | 0.5 | 0.2 | 0.1 |
| Amortization of intangible assets | | | | | | | 0.0 | 0.0 |
| Asset impairment charges | 0.5 | 1.4 | 0.0 | | | | | |
| Stock-based compensation | 61.3 | 40.7 | 24.8 | 20.3 | 12.2 | 9.9 | 4.9 | 2.7 |
| Change in working capital [+] | -80.0 | 40.9 | 52.2 | -15.3 | 30.6 | 5.9 | -2.1 | 1.7 |
| Accounts receivable | 4.3 | -42.3 | -1.4 | -3.7 | -0.1 | | | |
| Inventories | -15.4 | -7.2 | -7.2 | -6.0 | 0.0 | | | |
| Other current assets | -19.3 | -7.1 | -4.2 | -1.1 | -4.8 | -0.8 | -0.1 | 0.0 |
| Accounts payable | -53.8 | 63.5 | 40.0 | -14.8 | 28.5 | 8.4 | -0.9 | 1.3 |
| Deferred revenues | -1.4 | 11.1 | 14.3 | 1.1 | 0.0 | | | 0.1 |
| Other | 5.4 | 22.8 | 10.7 | 9.1 | 7.1 | -1.7 | -1.1 | 0.3 |
| Other operating activities | 85.7 | 65.8 | -28.9 | -4.7 | -3.0 | 1.6 | 2.4 | 2.0 |
| Cash from operations | -367.6 | -549.2 | -216.1 | -191.0 | -97.5 | -32.4 | -32.2 | -11.5 |
| |
| Capital expenditures [+] | -24.6 | -18.3 | -10.1 | -6.0 | -10.0 | -9.1 | -2.2 | -0.7 |
| Purchases of property and equipment | -24.6 | -18.3 | -10.1 | -6.0 | -10.0 | -9.1 | -2.2 | -0.7 |
| Sales of property and equipment | | 0.0 | | | | 0.1 | | |
| Purchases of intangible assets | -0.4 | -0.7 | -0.5 | -1.4 | -0.1 | 0.0 | 0.0 | |
| Purchases of short-term investments, net | 445.0 | 298.9 | -544.2 | 0.4 | -200.4 | | | |
| Purchases of short-term investments | -260.3 | -445.0 | -949.2 | -277.6 | -200.4 | | | |
| Sales of short-term investments | 705.3 | 743.9 | 405.0 | 278.0 | | | | |
| Other cash from investing | | -30.0 | | -7.8 | -2.1 | -1.4 | -0.5 | |
| Cash from investing | 420.0 | 250.0 | -554.8 | -14.9 | -212.6 | -10.4 | -2.7 | -0.7 |
| |
| Issuance of common stock, net | | 818.9 | 1,137.7 | 216.2 | 141.0 | 160.4 | | |
| Option exercises | 5.9 | 7.4 | 6.7 | 1.1 | 0.2 | 0.1 | | |
| Other cash from financing | 4.1 | 8.7 | 1.4 | 4.2 | 3.3 | 27.5 | 106.2 | 18.3 |
| Cash from financing | -1.7 | 820.2 | 1,132.4 | 219.3 | 144.1 | 187.9 | 106.2 | 18.3 |
| |
| Free cash flow | -392.2 | -567.5 | -226.2 | -197.0 | -107.6 | -41.5 | -34.4 | -12.2 |
| Per share (diluted) | ($0.41) | ($0.61) | ($0.29) | ($3.06) | ($2.04) | ($1.91) | ($3.64) | ($1.40) |
| |
| Cash paid for interest | | | 0.2 | 0.3 | 0.0 | | | |