Income Taxes - Narrative (FY) (Details) - USD ($) $ in Thousands |
Dec. 31, 2023 |
Dec. 31, 2022 |
May 31, 2022 |
|---|---|---|---|
| Income Tax Examination [Line Items] | |||
| Valuation allowance | $ 82,440 | $ 61,200 | |
| Costs resulting in ending gross deferred tax asset | 83,600 | $ 84,300 | |
| Operating lease obligations | 1,375 | 1,534 | |
| Deferred tax liability | (1,200) | (1,356) | |
| Federal | |||
| Income Tax Examination [Line Items] | |||
| Net operating loss carryforwards | 157,300 | 77,500 | |
| Research and development credit carryforwards | 4,000 | 3,700 | |
| State | |||
| Income Tax Examination [Line Items] | |||
| Net operating loss carryforwards | 55,900 | 46,400 | |
| Research and development credit carryforwards | $ 3,100 | $ 3,000 |