| In millions, except per share items | Dec-31-17 | Dec-31-16 | Dec-31-15 | Dec-31-14 | Dec-31-13 | Dec-31-12 |
| | 10-K | 10-K | 10-K | 10-K | S-1/A | S-1/A |
| Net income | 23.2 | 25.9 | 25.0 | 19.0 | 7.9 | 4.1 |
| Depreciation and amortization [+] | 0.8 | 0.6 | 0.3 | 0.2 | 0.1 | |
| Depreciation | 0.8 | 0.6 | 0.3 | 0.2 | 0.1 | |
| Asset impairment charges | 0.4 | | 0.4 | | | |
| Stock-based compensation | 0.9 | 0.8 | 0.6 | 0.2 | 0.0 | |
| Change in working capital [+] | -4.0 | 0.3 | 2.1 | 2.3 | 0.5 | |
| Other current assets | -0.3 | 0.1 | -0.1 | 0.3 | | |
| Accounts payable | -1.5 | 1.0 | -0.5 | 1.2 | 0.5 | |
| Deferred revenues | -1.1 | -1.1 | 2.1 | | | |
| Other | -1.1 | 0.2 | 0.6 | 0.8 | | |
| Other operating activities | -43.5 | -53.4 | -50.0 | -35.1 | -16.0 | |
| Cash from operations | -22.2 | -25.9 | -21.6 | -13.4 | -7.5 | |
| |
| Capital expenditures | -1.7 | -2.4 | -1.9 | -0.9 | -0.3 | |
| Purchases of property and equipment | -1.7 | -2.4 | -1.9 | -0.9 | -0.3 | |
| Other cash from investing | 0.0 | 0.2 | 0.7 | 0.7 | -1.8 | |
| Cash from investing | -1.7 | -2.1 | -1.2 | -0.2 | -2.0 | |
| |
| Issuance of common stock, net | 30.0 | | | | | |
| Option exercises | 0.2 | | 0.1 | 0.0 | | |
| Other cash from financing | 3.3 | 19.4 | 48.6 | 17.7 | 3.9 | |
| Cash from financing | 33.1 | 19.4 | 48.5 | 17.7 | 3.9 | |
| |
| Free cash flow | -24.0 | -28.2 | -23.5 | -14.3 | -7.8 | |
| Per share (diluted) | ($0.98) | ($1.74) | ($2.21) | ($28.53) | | |
| |
| Cash paid for interest | | | 0.0 | 0.1 | | |
| Cash paid for income taxes | | | 0.3 | | | |