Note 5 - Securities (Details) - Temporarily Impaired Securities (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Temporarily Impaired Securities:
Less Than 12 Months - Fair Value	$ 219,324	$ 53,709
Less Than 12 Months - Unrealized Loss	25,676	838
12 Months or More - Fair Value	3,632	615
12 Months or More - Unrealized Loss	532	175
US Government Agencies [Member]
Temporarily Impaired Securities:
Less Than 12 Months - Fair Value	156,170	44,351
Less Than 12 Months - Unrealized Loss	18,542	622
12 Months or More - Fair Value	2,608
12 Months or More - Unrealized Loss	408
States and Political Subdivisions [Member]
Temporarily Impaired Securities:
Less Than 12 Months - Fair Value	57,677	9,358
Less Than 12 Months - Unrealized Loss	6,593	216
12 Months or More - Fair Value	850	482
12 Months or More - Unrealized Loss	109	3
Corporate Securities [Member]
Temporarily Impaired Securities:
Less Than 12 Months - Fair Value	5,477
Less Than 12 Months - Unrealized Loss	541
Other Securities [Member]
Temporarily Impaired Securities:
12 Months or More - Fair Value	174	133
12 Months or More - Unrealized Loss	$ 15	$ 172