Note 8 - Stockholders' Equity - Summary of Investor Warrant Activity (Details) - Investor Warrant [Member] - $ / shares |
6 Months Ended | 12 Months Ended | |
|---|---|---|---|
Jun. 30, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
|
| Outstanding (in shares) | 3,246,690 | 2,691,459 | |
| Outstanding (in dollars per share) | $ 2.72 | $ 2.26 | $ 1.99 |
| Outstanding at December 31, 2020 (in dollars per share) | $ 2.02 | $ 3.59 | $ 2.94 |
| Granted (in shares) | 4,368,905 | 580,231 | |
| Exercised (in shares) | (3,188,190) | 0 | |
| Canceled/forfeited/expired (in shares) | 0 | (25,000) | |
| Outstanding (in shares) | 4,427,405 | 3,246,690 | 2,691,459 |
| X | ||||||||||
- Definition Represents sharebased compensation arrangement by sharebased payment award equity instruments other than options outstanding weighted average exercise price. No definition available.
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| X | ||||||||||
- Definition Represents Sharebased compensation arrangement by sharebased payment award equity instruments other than options outstanding weighted average remaining contractual term. No definition available.
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| X | ||||||||||
- Definition Number of non-option equity instruments exercised by participants. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Number of shares under non-option equity instrument agreements that were either cancelled or expired. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Net number of non-option equity instruments granted to participants. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Number of equity instruments other than options outstanding, including both vested and non-vested instruments. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Details
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