| In millions, except per share items | Jun-30-23 | Mar-31-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 |
| | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
| Net income | -7.1 | -6.4 | -5.5 | -8.3 | -8.1 | -7.3 | -8.5 | -7.3 |
| Depreciation and amortization [+] | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Depreciation | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Stock-based compensation | | | -1.8 | 0.6 | | | -2.0 | 0.5 |
| Change in working capital [+] | | | 0.3 | -0.8 | | | 0.1 | -0.7 |
| Other current assets | | | 0.5 | 0.4 | | | 0.1 | 0.5 |
| Accounts payable | | | 0.5 | -1.5 | | | -0.2 | -1.3 |
| Accrued expenses | | | | 0.3 | | | 0.2 | 0.1 |
| Other | | | -0.7 | | | | | |
| Other operating activities | -2.8 | -1.8 | 0.7 | -0.1 | 1.9 | 0.2 | 4.2 | 0.2 |
| Cash from operations | -9.9 | -8.2 | -6.3 | -8.6 | -6.2 | -7.1 | -6.2 | -7.2 |
| |
| Capital expenditures | 0.0 | 0.1 | 0.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Purchases of property and equipment | 0.0 | 0.1 | 0.2 | 0.0 | | | | |
| Purchases of short-term investments, net | 19.7 | 27.0 | 187.2 | -4.8 | 54.2 | | | |
| Purchases of short-term investments | | 9.0 | 187.2 | -6.8 | 54.2 | | | |
| Sales of short-term investments | 19.7 | 18.0 | | 2.0 | | | | |
| Other cash from investing | -0.1 | -18.1 | -235.7 | | -108.4 | | | |
| Cash from investing | 19.6 | 9.0 | -48.3 | -4.9 | -54.2 | 0.0 | 0.0 | 0.0 |
| |
| Repurchase of common stock, net | | | -103.0 | 51.2 | | | | |
| Option exercises | 0.0 | 0.1 | | 0.1 | 0.0 | | 0.0 | |
| Financing costs | | | 0.0 | | | | 0.1 | -0.1 |
| Other cash from financing | -7.7 | -1.6 | 103.7 | 4.2 | 56.0 | -0.6 | 13.8 | 0.1 |
| Cash from financing | -7.7 | -1.7 | 0.7 | 55.3 | 56.0 | -0.6 | 13.7 | 0.1 |
| |
| Free cash flow | -9.8 | -8.1 | -6.1 | -8.6 | -6.2 | -7.1 | -6.2 | -7.2 |
| Per share (diluted) | ($0.10) | ($0.08) | ($0.09) | ($0.13) | ($0.10) | ($0.23) | ($0.27) | ($0.34) |
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