Note 5 - Net Income per Common Share (Detail) - Net Income Per Common Share Calculation (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net income available to common shareholders (in Dollars)	$ 11,431	$ 7,492
Average common shares outstanding	23,199	20,111
Adjustment for common share equivalents	639	513
Average common shares outstanding-diluted	23,838	20,624
Diluted net income per common share (in Dollars per share)	$ 0.48	$ 0.36
Anti-dilutive shares	87,756	116,683
Basic net income per common share (in Dollars per share)	$ 0.49	$ 0.37