| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 |
| | 8-K | 10-K | 10-K | 10-K | S-1/A |
| Cash Flows From Operating Activities: | | | | | |
| Net loss | | -13.8 | -26.8 | -4.7 | |
| Adjustments to reconcile net loss to net cash used in operating activities: | | | | | |
| Depreciation and amortization | | 0.3 | 0.1 | 0.0 | |
| Stock-based compensation | | 8.5 | 0.8 | 0.0 | |
| Non-cash lease expense | | 0.3 | 0.2 | | |
| Unrealized gain from transactions denominated in a foreign currency | | 0.0 | | | |
| Changes in operating assets and liabilities: | | | | | |
| Other receivables | | -0.1 | 0.0 | 0.0 | |
| Other non-current assets | | -2.3 | -0.1 | 0.0 | |
| Accounts payable and other accrued liabilities | | 3.9 | 3.2 | 0.2 | |
| Accrued payroll and benefits | | 1.8 | 0.7 | 0.3 | |
| Other long-term liabilities | | 0.1 | | | |
| Net cash used in operating activities | | 3.7 | -21.1 | -3.7 | |
| |
| Cash Flows From Investing Activities: | | | | | |
| Purchases of property and equipment | | -0.6 | -0.5 | -0.2 | |
| Net cash provided by (used in) investing activities | | -0.6 | -0.5 | -0.2 | |
| |
| Cash Flows From Financing Activities: | | | | | |
| Proceeds from issuance of common stock upon follow-on public offering, net of paid issuance costs | | | 91.7 | | |
| Proceeds from sale of common stock under employee stock purchase plan | | 0.2 | | | |
| Proceeds from exercise of equity awards | | 0.3 | 0.0 | | |
| Payment of deferred offering costs | | -0.3 | | | |
| Net cash provided by financing activities | | 0.0 | 131.8 | 59.4 | |
| |
| Supplemental Disclosures Noncash Investing and Financing Activities: | | | | | |
| Additions of property and equipment included within accounts payable and other accrued liabilities | | 0.0 | 0.0 | 0.0 | |