Stockholders Equity (Stock-based Compensation Expense) (Details) - USD ($) $ in Thousands  | 
3 Months Ended | |
|---|---|---|
Mar. 31, 2023  | 
Mar. 31, 2022  | 
|
| Share-based Compensation | $ 235 | $ 664 | 
| General and administrative [Member] | ||
| Share-based Compensation | 109 | 147 | 
| Research and development [Member] | ||
| Share-based Compensation | $ 126 | $ 517 | 
| X | ||||||||||
- Definition Amount of noncash expense for share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
- Details 
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| X | ||||||||||
- Details 
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