Note 3 - Investment Securities (Detail) - Maturities of Investment Securities (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
One year or less	$ 55,281
One year or less	55,366
One year or less	7,876
One year or less	7,876
After one through five years	220,080
After one through five years	220,927
After one through five years	83,841
After one through five years	84,020
After five through ten years	159,352
After five through ten years	161,275
After five through ten years	74,840
After five through ten years	75,099
After ten years	75,917
After ten years	78,851
After ten years	21,741
After ten years	21,804
Other securities	0
Other securities	0
Other securities	15,817
Other securities	16,252
Total	510,630
Total	516,419
Total	204,115
Total	$ 205,051	$ 172,212