Summary of Significant Accounting Policies - Schedule of Property, Machinery and Equipment, net (Q3) (Details) |
Sep. 30, 2024 |
Dec. 31, 2023 |
|---|---|---|
| Computer equipment | ||
| Property, Plant and Equipment [Line Items] | ||
| Estimated Useful Life | 3 years | 3 years |
| Furniture and fixtures | ||
| Property, Plant and Equipment [Line Items] | ||
| Estimated Useful Life | 5 years | 5 years |
| Leasehold improvements | Minimum | ||
| Property, Plant and Equipment [Line Items] | ||
| Estimated Useful Life | 1 year | 1 year |
| Leasehold improvements | Maximum | ||
| Property, Plant and Equipment [Line Items] | ||
| Estimated Useful Life | 7 years | 7 years |
| Machinery and equipment | ||
| Property, Plant and Equipment [Line Items] | ||
| Estimated Useful Life | 7 years | 7 years |