| 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 | 0.3 | 0.2 | -20.3 | -16.1 | -18.0 | -14.8 | -11.9 | -9.5 |
| Depreciation and amortization | 0.9 | 0.9 | 0.7 | 0.7 | 0.6 | 0.5 | 0.3 | 0.2 |
| Stock-based compensation | 3.1 | 7.6 | 1.4 | 1.5 | 2.6 | 2.4 | 1.7 | 1.5 |
| Change in working capital [+] | 11.2 | 0.0 | 1.8 | 1.0 | 0.1 | -0.4 | 1.1 | 2.1 |
| Accounts receivable | -0.1 | 0.0 | 0.0 | | | | | |
| Other current assets | 0.4 | -0.2 | -0.3 | -0.1 | 0.0 | 0.0 | 0.0 | -0.1 |
| Deferred revenues | 10.0 | 0.0 | | | | | | |
| Other | 1.0 | 0.2 | 2.0 | 1.1 | 0.1 | -0.4 | 1.1 | 2.2 |
| Other operating activities | -30.9 | -29.6 | 0.0 | 0.2 | 0.0 | 0.0 | 0.0 | -2.8 |
| Cash from operations | -15.3 | -20.9 | -16.5 | -12.7 | -14.7 | -12.2 | -8.9 | -8.5 |
| |
| Capital expenditures [+] | -1.6 | -1.0 | -1.9 | -0.5 | -0.3 | -1.4 | -0.4 | -0.1 |
| Purchases of property and equipment | -1.6 | -1.0 | -1.9 | -0.5 | -0.3 | -1.4 | -0.4 | -0.1 |
| Sales of property and equipment | | | 0.3 | | | | | |
| Purchases of intangible assets | | | | | | | | -0.1 |
| Cash from investing | -1.6 | -1.0 | -1.6 | -0.5 | -0.3 | -1.4 | -0.4 | -0.1 |
| |
| Issuance of common stock, net | 6.7 | 23.2 | 21.1 | 16.6 | 17.2 | 1.0 | 25.3 | 12.5 |
| Financing costs | | | | | | -0.1 | | |
| Other cash from financing | 0.2 | -0.4 | -0.5 | 0.3 | 0.7 | 0.9 | -0.1 | -0.1 |
| Cash from financing | 6.9 | 22.9 | 20.6 | 16.9 | 18.0 | 2.0 | 25.2 | 12.4 |
| |
| Free cash flow | -16.8 | -21.8 | -18.4 | -13.3 | -15.0 | -13.6 | -9.3 | -8.6 |
| Per share (diluted) | ($0.31) | ($0.41) | ($0.41) | ($0.34) | ($0.48) | ($0.52) | ($0.40) | ($0.49) |
| |
| Cash paid for interest | 0.2 | 0.2 | 0.1 | 0.1 | 0.1 | 0.1 | 0.0 | 0.0 |
| Cash paid for income taxes | | | | | | | | 0.0 |