Note 8 - Earnings Per Share - Reconciliation of Number of Shares Used in Computation of Basic and Diluted Earnings (Loss) Per Share (Details) - shares shares in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Weighted average number of shares used in computation of basic earnings per share (in shares)	49,173	47,244
Add:
Additional shares from the assumed exercise of employee stock options (in shares)	609	835
Weighted average number of shares used in computation of diluted earnings per share (in shares)	49,782	48,079

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
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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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

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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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-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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