| 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 | 10-K | 10-K | 10-K |
| Net income | -389.0 | -215.3 | -127.3 | -121.7 | -106.3 | -127.8 | 16.5 | -37.5 |
| Depreciation and amortization [+] | 5.8 | 2.3 | 1.8 | 1.3 | 1.2 | 1.9 | 0.7 | 0.6 |
| Depreciation | 5.8 | 2.3 | 1.8 | 1.3 | 1.2 | 1.9 | 0.7 | 0.6 |
| Stock-based compensation | | | | 10.8 | 9.8 | 9.0 | 7.1 | 4.6 |
| Change in working capital [+] | -82.5 | 1.1 | 86.9 | -4.6 | -9.3 | 0.5 | 12.1 | 37.2 |
| Accounts receivable | | | | -2.9 | -1.1 | -1.1 | 0.0 | 46.6 |
| Other current assets | | | | -3.9 | 1.8 | -2.2 | -0.7 | -0.4 |
| Accounts payable | 4.5 | 1.1 | -0.1 | 4.4 | -1.5 | 1.5 | 1.7 | 0.8 |
| Accrued expenses | | | | -2.2 | -2.1 | 0.8 | 8.9 | 3.0 |
| Deferred revenues | -87.0 | | 87.0 | | -6.5 | 1.5 | 2.2 | -12.7 |
| Other operating activities | 166.1 | 69.5 | 47.5 | 23.3 | 3.4 | 14.6 | 0.5 | 0.0 |
| Cash from operations | -299.5 | -142.5 | 8.9 | -90.9 | -101.2 | -101.8 | 37.0 | 4.9 |
| |
| Capital expenditures [+] | 11.3 | 48.9 | 11.1 | -2.6 | -0.9 | -2.9 | -1.6 | -0.6 |
| Purchases of property and equipment | 11.3 | 48.9 | 11.1 | -2.6 | -0.9 | -2.9 | -1.6 | -0.6 |
| Sales of property and equipment | | | | | 0.0 | | 0.0 | 0.0 |
| Purchases of short-term investments, net | 1,460.0 | 951.2 | 686.2 | -72.1 | 6.0 | -63.0 | -50.5 | 16.6 |
| Purchases of short-term investments | 855.4 | 525.0 | 435.8 | -277.9 | -240.2 | -240.4 | -145.2 | -115.6 |
| Sales of short-term investments | 604.6 | 426.1 | 250.4 | 205.8 | 246.2 | 177.5 | 94.6 | 132.2 |
| Other cash from investing | -1,733.5 | -1,147.8 | -893.8 | | | | | |
| Cash from investing | -262.1 | -147.8 | -196.5 | -74.7 | 5.1 | -65.8 | -52.1 | 16.1 |
| |
| Issuance of common stock, net | | | | 36.2 | | 112.2 | | 8.7 |
| Option exercises | 17.5 | 12.4 | 9.1 | 1.4 | 3.2 | | | |
| Other cash from financing | 533.7 | 332.4 | 243.2 | 125.0 | 16.4 | 113.7 | 16.9 | 15.2 |
| Cash from financing | 516.2 | 320.0 | 234.1 | 159.8 | 13.1 | 225.9 | 16.9 | 23.9 |
| |
| Free cash flow | -288.2 | -93.7 | 20.0 | -93.5 | -102.1 | -104.6 | 35.4 | 4.3 |
| Per share (diluted) | ($3.21) | ($1.22) | $0.31 | ($1.62) | ($1.88) | ($2.12) | $0.83 | $0.11 |
| |
| Cash paid for interest | 15.2 | 9.2 | 9.6 | 4.1 | 2.9 | 2.1 | 1.9 | 0.1 |
| Cash paid for income taxes | | | | | | 0.0 | 0.0 | 0.0 |