| In millions, except per share items | Jun-30-23 | Mar-31-23 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 |
| | 10-Q | 10-Q | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q |
| Cash flows from operating activities: | | | | | | | | |
| Net loss | | | -15.7 | -13.1 | -12.4 | -11.8 | -12.4 | -13.3 |
| Adjustments to reconcile net loss to net cash used in operating activities: | | | | | | | | |
| Stock-based compensation | | | 1.9 | 1.7 | 1.6 | 1.3 | 1.1 | 1.4 |
| Depreciation and amortization | | | 0.1 | 0.1 | 0.1 | | 0.1 | 0.0 |
| Amortization of debt discounts | | | 0.2 | | | | | |
| Change in fair value of warrant liabilities | | | -0.3 | | | | | 0.0 |
| Changes in operating assets and liabilities: | | | | | | | | |
| Accounts receivable | | | 0.0 | 0.2 | -0.1 | -0.1 | 0.0 | -0.3 |
| Inventories | | | -3.3 | -2.7 | -2.9 | -2.1 | -1.4 | -0.8 |
| Prepaid expenses and other assets | | | 0.4 | 0.9 | 0.4 | -0.2 | -0.5 | -0.8 |
| Other assets | | | 0.2 | 0.0 | | | | |
| Accounts payable | | | 1.8 | 0.5 | 1.0 | 0.9 | -0.1 | -0.5 |
| Accrued liabilities | | | -0.9 | -1.2 | -0.1 | 0.0 | 1.1 | 2.0 |
| Other liabilities | | | -0.1 | -0.1 | 0.0 | | | |
| Net cash used in operating activities | | | -15.8 | -14.5 | -12.8 | -11.5 | -10.9 | -10.4 |
| |
| Cash flows from investing activities: | | | | | | | | |
| Purchases of property and equipment | | | 0.0 | -0.1 | -0.1 | -0.1 | -0.1 | -0.1 |
| Net cash used in investing activities | | | 0.0 | -0.1 | -0.1 | -0.1 | -0.1 | -0.1 |
| |
| Cash flows from financing activities: | | | | | | | | |
| Net cash provided by (used in) financing activities | | | 2.5 | 9.0 | 12.2 | 17.3 | 18.0 | 8.6 |
| |
| Supplemental disclosure of cash flow information: | | | | | | | | |
| Cash paid for interest | | | 0.0 | | 0.0 | | 0.0 | 0.0 |
| Cash paid for income taxes | | | | 0.0 | | | | 0.0 |
| Noncash Investing and Financing Activities: | | | | | | | | |