Note 10 - Per Share Data - Weighted Average Number of Common Shares (Details) - shares	3 Months Ended	6 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Basic weighted average shares outstanding (in shares)	12,880,179	12,239,758	12,868,356	12,239,259
Dilutive effect of outstanding restricted share units (in shares)	57,932	21,895	50,727	20,200
Weighted average dilutive shares outstanding (in shares)	12,938,111	12,261,653	12,919,083	12,259,459

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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