| 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 | 10-K | 10-K |
| Net income | -55.4 | -139.1 | -224.7 | -68.8 | -64.1 | -38.5 | -40.4 |
| Depreciation and amortization | 14.9 | 18.7 | 22.6 | 24.3 | 34.6 | 19.4 | 7.6 |
| Asset impairment charges | | | | | 3.4 | 2.7 | 1.8 |
| Stock-based compensation | 53.4 | 47.5 | 40.2 | 37.6 | 30.2 | 10.9 | 8.5 |
| Tax benefit from stock-based compensation | | | | | | -2.3 | |
| Deferred taxes | | | | | 0.1 | -0.4 | -0.1 |
| Change in working capital [+] | -4.3 | 55.1 | 37.9 | 24.0 | 9.1 | -19.9 | 5.5 |
| Accounts receivable | -2.2 | -0.6 | -2.5 | -0.3 | -2.1 | -0.8 | -1.4 |
| Other current assets | 4.7 | -8.3 | 4.9 | 1.9 | -5.6 | -4.3 | -1.9 |
| Accounts payable | -0.1 | -0.8 | 0.2 | 0.7 | -0.5 | 0.4 | 0.2 |
| Other | -6.8 | 64.9 | 35.4 | 21.7 | 17.2 | -15.1 | 8.5 |
| Other operating activities | 0.1 | 103.6 | -33.9 | 12.8 | -6.2 | 57.9 | 19.7 |
| Cash from operations | 8.6 | 85.8 | -158.0 | 30.0 | 7.2 | 29.8 | 2.8 |
| |
| Capital expenditures [+] | -4.5 | -2.5 | -6.3 | -13.6 | -12.7 | -8.7 | -8.5 |
| Purchases of property and equipment | -1.4 | -1.0 | -1.7 | -5.9 | -5.4 | -2.5 | -3.0 |
| Capitalized product costs | -3.0 | -1.5 | -4.6 | -7.7 | -7.2 | -6.1 | -5.5 |
| Acquisitions | -1.1 | | -6.4 | | 12.6 | -132.0 | -1.7 |
| Purchases of short-term investments | -83.9 | | | | | | |
| Purchases of short-term investments | -83.9 | | | | | | |
| Cash from investing | -89.5 | -2.5 | -12.7 | -13.6 | 0.0 | -140.7 | -10.2 |
| |
| Issuance of common stock, net | | | | | 241.0 | | |
| Option exercises | 3.1 | 18.5 | 19.3 | 40.7 | 8.1 | 1.8 | 2.9 |
| Financing costs | | -5.7 | -18.9 | -0.5 | | | |
| Other cash from financing | 1.1 | 64.0 | 255.4 | 7.4 | 7.2 | 161.3 | 5.2 |
| Cash from financing | -2.1 | 51.2 | 255.0 | -32.8 | 240.1 | 159.5 | 2.3 |
| |
| Free cash flow | 7.2 | 84.8 | -159.7 | 24.1 | 1.7 | 27.3 | -0.2 |
| Per share (diluted) | $0.04 | $0.88 | ($1.84) | $0.20 | ($0.15) | $1.08 | ($0.35) |
| |
| Cash paid for interest | 9.2 | 9.6 | 6.8 | 10.7 | 7.6 | 0.9 | |
| Cash paid for income taxes | 0.7 | 0.1 | 0.8 | 1.1 | 0.2 | 0.1 | 0.1 |