Note 4 - Earnings per Share (Details) - Earnings per Share (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Note 4 - Earnings per Share (Details) - Earnings per Share [Line Items]
Net income (in Dollars)	$ 35,980us-gaap_NetIncomeLoss	$ 31,259us-gaap_NetIncomeLoss
Basic weighted-average number of common shares outstanding	79,835,628	79,595,757
Dilutive effect of weighted-average outstanding common share equivalents
Diluted weighted-average number of common shares outstanding	80,309,383	80,039,382
Average stock options and warrants with anti-dilutive effect	1,670,231	1,985,848
Basic (in Dollars per share)	$ 0.45us-gaap_EarningsPerShareBasic	$ 0.39us-gaap_EarningsPerShareBasic
Diluted (in Dollars per share)	$ 0.45us-gaap_EarningsPerShareDiluted	$ 0.39us-gaap_EarningsPerShareDiluted
Warrant [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	344,919	298,535
Equity Option [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	108,457	101,698
Restricted Stock Units (RSUs) [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	20,379	43,392

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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