Note 3 - Securities (Detail) - Changes In Credit Losses Recognized In Earnings (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Cumulative amount recognized at the beginning of the year	$ 36,525		$ 35,589		$ 30,839
Cumulative amount recognized at the end of the year	38,803		36,525		35,589
Credit losses included in earnings (1):
Losses recognized on securities that previously had credit losses	2,278	[1]	936	[1]	4,421	[1]
Losses recognized on securities that did not previously have credit losses	1,391	[1]		[1]	329	[1]
Reduction for securities sold during the year	$ (1,391)

[1] Included in securities (losses) gains in the Condensed Consolidated Statements of Income.