Note 8 - Income Per Share - Weighted Average Number of Shares Used to Compute Net EPS (Details) - shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Basic (in shares)	7,347	7,239	7,336	7,228
Weighted average common equivalent shares due to stock options and RSUs (in shares)	66	84	72	84
Diluted weighted average common shares outstanding (in shares)	7,413	7,323	7,408	7,312

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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