Note 4 - Earnings Per Share (Details) - Earnings Per Share - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Note 4 - Earnings Per Share (Details) - Earnings Per Share [Line Items]
Net income (in Dollars)	$ 46,163	$ 35,980
Weighted-average shares:
Basic weighted-average number of common shares outstanding	79,734,519	79,835,628
Dilutive effect of weighted-average outstanding common share equivalents
Diluted weighted-average number of common shares outstanding	80,393,849	80,309,383
Average stock options and warrants with anti-dilutive effect	359,544	1,670,231
Earnings per common share:
Basic (in Dollars per share)	$ 0.58	$ 0.45
Diluted (in Dollars per share)	$ 0.57	$ 0.45
Warrant [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	452,368	344,919
Employee Stock Option [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	83,018	108,457
Restricted Stock Units (RSUs) [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	123,944	20,379

The average shares of stock options and warrants with anti-dilutive effect.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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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 portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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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