Note L - Dilutive Effect of Stock Options and Awards (Details) - shares shares in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Basic weighted-average shares outstanding (in shares)	19,335	19,608	19,755
Effect of potential exercise of stock options and RSUs (in shares)	328	389	431
Diluted weighted-average shares outstanding (in shares)	19,663	19,997	20,186

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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