Accrued Expense (Details) - USD ($) $ in Thousands |
Dec. 31, 2021 |
Dec. 31, 2020 |
|---|---|---|
| Accrued Expense | ||
| Accrued expense | $ 770 | $ 975 |
| Accrued clinical trial expenses | 400 | |
| Accrued vacation and bonus expenses | 400 | 400 |
| Manufacturing expenses | 100 | 100 |
| Accrued legal and patent fees | 100 | |
| Other accrued expenses | $ 100 | $ 100 |