Note 5 - Earnings per Share (Details) - Earnings per Share - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Note 5 - Earnings per Share (Details) - Earnings per Share [Line Items]
Net income (in Dollars)	$ 38,483	$ 35,909	$ 119,663	$ 102,252
Weighted-average shares:
Basic weighted-average number of common shares outstanding	81,475,288	79,677,952	80,422,711	79,639,202
Dilutive effect of weighted-average outstanding common share equivalents
Diluted weighted-average number of common shares outstanding	82,285,478	80,176,100	81,105,190	80,087,819
Average stock options and warrants with anti-dilutive effect	760,291	1,990,358	1,082,400	1,993,384
Earnings per common share:
Basic (in Dollars per share)	$ 0.47	$ 0.45	$ 1.49	$ 1.28
Diluted (in Dollars per share)	$ 0.47	$ 0.45	$ 1.48	$ 1.28
Warrant [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	606,803	346,101	507,002	306,306
Equity Option [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	123,910	109,803	124,135	103,022
Restricted Stock Units (RSUs) [Member]
Dilutive effect of weighted-average outstanding common share equivalents
Dilutive effect of weighted-average outstanding common share equivalents	79,477	42,244	51,343	39,289