Note 10 - Per Share Data - Weighted Average Number of Common Shares (Details) - shares	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Basic weighted average shares outstanding (in shares)	12,955,198	12,284,727	12,897,303	12,254,415
Dilutive effect of outstanding restricted share units (in shares)	63,416	32,723	53,628	24,165
Weighted average dilutive shares outstanding (in shares)	13,018,614	12,317,450	12,950,931	12,278,580

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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