Note 10 - Per Share Data - Weighted Average Number of Common Shares (Details) - shares	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Basic weighted average shares outstanding (in shares)	12,284,727	12,009,181	12,254,415	11,972,600
Dilutive effect of outstanding restricted stock awards (in shares)	32,723	141,914	24,165	116,610
Weighted average dilutive shares outstanding (in shares)	12,317,450	12,151,095	12,278,580	12,089,210

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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