| In millions, except per share items | Dec-31-22 | Dec-05-22 | Dec-31-21 | Dec-05-21 | Dec-31-20 | Dec-31-19 |
| | 10-K | 8-K | 10-K | 8-K | 10-K | 10-K |
| Cash flows from operating activities: | | | | | | |
| Net loss | -147.3 | -147.3 | -101.9 | -101.9 | -25.6 | -19.6 |
| Adjustments to reconcile net loss to net cash used in operating activities: | | | | | | |
| Depreciation and amortization | 3.3 | 3.3 | 1.1 | 1.1 | 0.8 | 0.6 |
| Impairment of inventories | 1.7 | | | | | |
| Loss on write down of fixed assets | | | 0.1 | | | |
| Change in fair value of warrant liability | -1.0 | | -2.0 | | | |
| Stock-based compensation | 24.2 | 24.2 | 22.2 | 22.2 | 3.8 | 2.2 |
| Amortization of right-of-use assets | 2.9 | | 1.9 | | | |
| Realized loss on available-for-sale securities | 0.0 | | | | | |
| Amortization of premium on available-for-sale securities | 0.4 | | 1.5 | | | |
| Accounts receivable | -0.5 | -0.5 | -2.2 | -2.2 | 0.2 | -0.4 |
| Inventories | -2.6 | -2.6 | -0.8 | -0.8 | -0.9 | 0.6 |
| Other current assets | 3.6 | 3.6 | -7.3 | -7.3 | -3.5 | -0.6 |
| Other noncurrent assets | 0.0 | 0.0 | -0.8 | -0.8 | 0.0 | 0.0 |
| Accounts payable | 1.3 | 1.3 | 2.7 | 2.7 | 1.4 | 0.2 |
| Accrued liabilities | 5.0 | 5.0 | 3.2 | 3.2 | 2.3 | 0.2 |
| Accrued employee costs | 2.5 | | 1.5 | | 0.3 | 0.2 |
| Lease liability | -2.9 | | -1.8 | | | |
| Other current liabilities | -0.5 | -0.5 | 0.5 | 0.5 | 0.0 | 0.2 |
| Other noncurrent liabilities | | | | | 0.0 | -0.1 |
| Net cash used in operating activities | -109.9 | -109.9 | -82.1 | -82.1 | -21.2 | -16.4 |
| |
| Cash flows from investing activities: | | | | | | |
| Purchase of property, plant, and equipment | -7.4 | | -3.9 | | -0.9 | -0.4 |
| Purchase of available-for-sale securities | -210.2 | -210.2 | -571.9 | -571.9 | | |
| Proceeds from sale of available-for-sale securities | | | 20.1 | | | |
| Proceeds from maturities of available-for-sale securities | 328.5 | | 171.6 | | | |
| Purchase of intangible assets | | | -4.5 | | | |
| Net cash provided by (used in) investing activities | 110.9 | 110.9 | -388.6 | -388.6 | -0.9 | -0.4 |
| |
| Cash flows from financing activities: | | | | | | |
| Proceeds from business combination and private offering | | | 560.8 | | | |
| Transaction costs related to business combination and private offering | | | -47.5 | | | |
| Payments of taxes withheld on net settled vesting of restricted stock units | -0.7 | | -1.3 | | | |
| Proceeds from the issuance of Series B Preferred Stock | | | | | | |
| Proceeds from exercise of stock options | 0.4 | 0.4 | 0.9 | 0.9 | 0.1 | 0.0 |
| Proceeds from exercise of warrants | 0.0 | | | | | |
| Financing costs incurred | | | | | | |
| Net cash provided by (used in) financing activities | -0.4 | -0.4 | 512.9 | 512.9 | 0.1 | 36.0 |
| Net increase (decrease) in cash and cash equivalents | 0.6 | | 42.2 | | -22.0 | 19.2 |
| |
| Supplemental disclosures of cash flow information: | | | | | | |
| Supplemental disclosure of noncash investing and financing activities: | | | | | | |
| Unpaid property, plant and equipment purchases | 0.1 | | 0.8 | | 0.0 | 0.0 |
| Private placement of warrants acquired as part of merger | | | 3.0 | | | |
| Right-of-use asset obtained in exchange for lease liability | | | 10.5 | | | |
| Non-cash lease adoption | | | 1.7 | | | |