Note 5 - Net Income per Common Share (Details) - Net Income per Common Share Calculation (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Net Income per Common Share Calculation [Abstract]
Net income available to common shareholders (in Dollars)	$ 12,358	$ 11,431
Average common shares outstanding	25,928	25,519
Adjustment for common share equivalents	647	703
Average common shares outstanding-diluted	26,575	26,222
Diluted net income per common share (in Dollars per share)	$ 0.47	$ 0.44
Anti-dilutive shares	21,000	101,466
Basic net income per common share (in Dollars per share)	$ 0.48	$ 0.45