| In millions, except per share items | Jun-30-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 |
| | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q |
| Cash flows from operating activities: | | | | | | | | |
| Net loss | -4.9 | -4.4 | -6.4 | -4.9 | -3.8 | -5.8 | -3.8 | -5.9 |
| Adjustments to reconcile net loss to net cash used in operating activities: | | | | | | | | |
| Depreciation of property and equipment | | 0.0 | 0.0 | 0.0 | 0.0 | 0.2 | 0.2 | 0.2 |
| Redeemable warrants valuation adjustment | | | | 0.0 | | | | |
| Amortization of patent, trademark rights | | 0.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Changes in ROU assets | | 0.0 | 0.0 | -0.7 | 0.0 | 0.0 | 0.0 | 0.0 |
| Gain from sale of income tax operating losses | | | | -0.4 | | | | |
| Equity-based compensation | | 0.2 | 0.3 | 0.3 | 0.2 | 0.2 | 0.3 | 0.5 |
| (Loss) on sale of marketable securities | | | | 1.4 | | | | |
| Change in assets and liabilities: | | | | | | | | |
| Funds Receivable from New Jersey net operating loss | | -1.7 | | 1.6 | | -1.6 | | 1.1 |
| Prepaid expenses and other current assets and other non-current assets | | 0.3 | -0.4 | -0.1 | 0.0 | 1.6 | 0.0 | 0.0 |
| Lease liability | | 0.0 | 0.0 | 0.7 | 0.0 | 0.0 | 0.0 | 0.0 |
| Other Assets | | 0.0 | | -0.1 | | | | |
| Accounts payable | | -0.6 | 0.2 | 0.3 | 0.2 | -0.2 | -0.1 | 0.3 |
| Accrued expenses | | -1.0 | 1.3 | 0.2 | -0.1 | 0.1 | 0.0 | -0.1 |
| Net cash used in operating activities | -4.9 | -6.1 | -5.0 | -2.3 | -2.8 | -5.7 | -3.5 | -1.7 |
| |
| Cash flows from investing activities: | | | | | | | | |
| Proceeds from sale of marketable securities | | 1.0 | 0.4 | 8.3 | 0.4 | 21.4 | -0.8 | -0.4 |
| Purchase of marketable securities | | -1.1 | -0.4 | -0.5 | -0.7 | -20.9 | 0.5 | -0.9 |
| Proceeds from sale of property and equipment | | 3.6 | 0.3 | | | | | 0.2 |
| Purchase of patent and trademark rights | | | | -0.1 | | | | |
| Net cash (used in) provided by investing activities | | 3.4 | 0.3 | 7.7 | -0.3 | 0.4 | -0.4 | -1.2 |
| |
| Cash flows from financing activities: | | | | | | | | |
| Proceeds from sale of stock, net of issuance costs | | | 0.0 | 0.1 | | 0.1 | 0.0 | |
| Net cash provided by financing activities | | | 0.0 | 0.1 | | 0.1 | 0.0 | -4.8 |
| Net (decrease) increase in cash and cash equivalents | | | | 2.4 | | | | |
| |
| Supplemental disclosures of non-cash investing and financing cash flow information: | | | | | | | | |
| Operating lease-Right of Use Assets | | | | 0.8 | | | | |
| Unrealized gain (loss) on marketable securities | | | | | | | | |
| Conversion of Series B preferred | | | | | | | | |