Note 4 - Stock-based Compensation - Nonvested Option Awards Activity (Details) - $ / shares |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2019 |
Mar. 31, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Nonvested, Shares, Beginning Balance (in shares) | 41,000 | 148,500 | 148,500 | ||
| Nonvested, weighted average grant date fair value (in dollars per share) | $ 0.17 | $ 0.20 | $ 0.20 | ||
| Granted, shares (in shares) | 3,000 | 30,000 | 3,000 | 160,000 | |
| Granted, weighted average grant date fair value (in dollars per share) | $ 0.11 | $ 0.11 | |||
| Vested, shares (in shares) | (12,500) | (107,500) | |||
| Vested, weighted average grant date fair value (in dollars per share) | $ 0.17 | $ 0.21 | |||
| Options forfeited, shares (in shares) | (2,500) | ||||
| Forfeited, weighted average grant date fair value (in dollars per share) | $ 0.21 | ||||
| Nonvested, shares (in shares) | 29,000 | 41,000 | 29,000 | ||
| Nonvested, weighted average grant date fair value (in dollars per share) | $ 0.16 | $ 0.17 | $ 0.16 | ||
| X | ||||||||||
- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Gross number of share options (or share units) granted during the period. No definition available.
|
| X | ||||||||||
- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of non-vested options outstanding. No definition available.
|
| X | ||||||||||
- Definition Weighted average grant-date fair value of non-vested options forfeited. No definition available.
|
| X | ||||||||||
- Definition Weighted average grant-date fair value of non-vested options outstanding. No definition available.
|
| X | ||||||||||
- Definition Number of options vested. No definition available.
|
| X | ||||||||||
- Definition Weighted average grant-date fair value of options vested. No definition available.
|