Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	$ 92,395	$ 334,326
Less than 12 Months, Unrealized Losses	369	9,303
12 Months or More, Fair Value	195,534	48,069
12 Months or More, Unrealized Losses	4,482	3,609
Total, Fair Value	287,929	382,395
Total, Unrealized Losses	4,851	12,912
US Government-sponsored Enterprises Debt Securities [Member]
Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	8,609	65,094
Less than 12 Months, Unrealized Losses	32	2,434
12 Months or More, Fair Value	66,628	11,830
12 Months or More, Unrealized Losses	1,404	721
Total, Fair Value	75,237	76,924
Total, Unrealized Losses	1,436	3,155
US States and Political Subdivisions Debt Securities [Member]
Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	11,006	48,715
Less than 12 Months, Unrealized Losses	20	1,594
12 Months or More, Fair Value	25,704	15,095
12 Months or More, Unrealized Losses	423	803
Total, Fair Value	36,710	63,810
Total, Unrealized Losses	443	2,397
Residential Mortgage Backed Securities [Member]
Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	72,689	219,032
Less than 12 Months, Unrealized Losses	315	5,199
12 Months or More, Fair Value	96,817	16,306
12 Months or More, Unrealized Losses	2,321	1,033
Total, Fair Value	169,506	235,338
Total, Unrealized Losses	2,636	6,232
Commercial Mortgage Backed Securities [Member]
Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	0	689
Less than 12 Months, Unrealized Losses	0	59
12 Months or More, Fair Value	711	0
12 Months or More, Unrealized Losses	26	0
Total, Fair Value	711	689
Total, Unrealized Losses	26	59
Corporate Debt Securities [Member]
Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	52	80
Less than 12 Months, Unrealized Losses	1	0
12 Months or More, Fair Value	5,574	4,816
12 Months or More, Unrealized Losses	302	1,049
Total, Fair Value	5,626	4,896
Total, Unrealized Losses	303	1,049
Mutual Funds And Equity Securities [Member]
Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	39	716
Less than 12 Months, Unrealized Losses	1	17
12 Months or More, Fair Value	100	22
12 Months or More, Unrealized Losses	6	3
Total, Fair Value	139	738
Total, Unrealized Losses	$ 7	$ 20