Note 4 - Stock-based Compensation - Valuation Assumptions (Details) |
3 Months Ended | |
|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Dividend yield | 0.00% | |
| Vesting period (years) (Year) | 4 years 284 days | 3 years |
| Minimum [Member] | ||
| Expected volatility | 39.57% | |
| Risk-free interest rate | 1.65% | |
| Expected life (years) (Year) | 4 years | |
| Vesting period (years) (Year) | 3 years | |
| Maximum [Member] | ||
| Expected volatility | 41.59% | |
| Risk-free interest rate | 1.69% | |
| Expected life (years) (Year) | 6 years | |
| Vesting period (years) (Year) | 5 years | |
| X | ||||||||||
- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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- Details
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