Note 7 - Stockholders' Equity - Basic and Diluted Earnings Per Share Calculation (Details) - shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Weighted average shares outstanding for basic calculation (in shares)	14,519	14,203	14,551	14,196
Add: Effect of dilutive stock awards (in shares)
Weighted average shares outstanding, adjusted for diluted calculation (in shares)	14,519	14,203	14,551	14,196

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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