Note 4 - Earnings Per Share (Details) - Earnings Per Share Calculation (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator for basic and diluted earnings per share –
Net income available to common shareholders (in Dollars)	$ 19,838	$ 5,632	$ 31,852	$ 19,179
Denominator–
Denominator for basic earnings per share – weighted average shares outstanding	39,751	39,552	39,544	39,337
Effect of dilutive securities–
Employee and director stock options and restricted share awards	1,098	1,029	1,138	1,109
Denominator for diluted earnings per share – adjusted weighted average shares outstanding and assumed conversions	40,849	40,581	40,682	40,446
Basic earnings per common share (in Dollars per share)	$ 0.50	$ 0.14	$ 0.81	$ 0.49
Diluted earnings per common share and common share equivalents (in Dollars per share)	$ 0.49	$ 0.14	$ 0.78	$ 0.47