Note 7 - Stock-based Compensation - Valuation Assumptions of Stock Options (Details) - Black Scholes Weighted Average Assumptions [Member] - Employee Stock Option [Member] - $ / shares |
12 Months Ended | ||
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Dec. 31, 2017 |
Jan. 01, 2017 |
Jan. 03, 2016 |
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| Expected dividend yield | 0.00% | ||
| Expected volatility | 43.80% | ||
| Expected forfeiture | 29.00% | ||
| Risk-free interest rate | 1.33% | ||
| Expected stock option life in years (Year) | 4 years | ||
| Weighted-average stock option fair value per stock option granted (in dollars per share) | $ 0.48 | ||
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- Definition The estimated forfeiture rate of the underlying shares over the option's term. No definition available.
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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://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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- 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://www.xbrl.org/2003/role/presentationRef
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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