Note 12 - Stock Warrants  | 
9 Months Ended | ||
|---|---|---|---|
Sep. 30, 2021  | |||
| Notes to Financial Statements | |||
| Stock Warrants Disclosure [Text Block] | 
   
 
 As of September 30, 2021, there are 972,324 warrants outstanding to purchase Navidea's Common Stock. The warrants are exercisable at prices ranging from $0.20 to $49.80 per share with a weighted average exercise price of $17.97 per share. The warrants have remaining outstanding terms ranging from 5 months to 13.9 years.  | 
| X | ||||||||||
- Definition The entire disclosure for stock warrants. No definition available. 
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| X | ||||||||||
- References No definition available. 
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