Note 11 - Earnings Per Common Share (Detail) - Earnings per common share and diluted earnings per common share (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Net income applicable to common equity (numerator) (in Dollars)	$ 22,432	$ 23,709	$ 66,083	$ 70,846
Weighted average number of common shares outstanding - basic	28,433	29,127	28,739	29,187
Add exercise of options reduced by the number of shares that could have been purchased with the proceeds of such exercise	65	258	140	328
Weighted average number of common shares outstanding - diluted (denominator)	28,498	29,385	28,879	29,515
Diluted earnings per common share (in Dollars per share)	$ 0.79	$ 0.81	$ 2.29	$ 2.40
Basic earnings per common share (in Dollars per share)	$ 0.79	$ 0.81	$ 2.30	$ 2.43