Risks, Liquidity, and Going Concern (Q1) (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Mar. 05, 2021 |
Mar. 31, 2026 |
Mar. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Risks, Liquidity, and Going Concern | |||||
| Accumulated deficit | $ (712,316) | $ (704,757) | $ (659,235) | ||
| Sale of common stock, net of issuance costs | 8,742 | ||||
| Net Income (Loss) | (7,559) | $ (15,405) | (45,522) | (64,767) | |
| Cash and cash equivalents | 33,336 | $ 46,303 | $ 37,573 | ||
| ATM Facility [Member] | |||||
| Risks, Liquidity, and Going Concern | |||||
| Remaining capacity available to be sold | $ 15,800 | ||||
| ATM Facility [Member] | Maximum | |||||
| Risks, Liquidity, and Going Concern | |||||
| Sale of common stock, net of issuance costs | $ 125,000 | ||||
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- Definition The remaining capacity of value of shares available to be sold. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of accumulated undistributed earnings (deficit). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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