Note 6 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 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	$ 250,289	$ 334,326
Less than 12 Months, Unrealized Losses	5,557	9,303
12 Months or More, Fair Value	49,224	48,069
12 Months or More, Unrealized Losses	2,774	3,609
Total, Fair Value	299,513	382,395
Total, Unrealized Losses	8,331	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	61,969	65,094
Less than 12 Months, Unrealized Losses	1,645	2,434
12 Months or More, Fair Value	13,896	11,830
12 Months or More, Unrealized Losses	656	721
Total, Fair Value	75,865	76,924
Total, Unrealized Losses	2,301	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	38,839	48,715
Less than 12 Months, Unrealized Losses	825	1,594
12 Months or More, Fair Value	14,121	15,095
12 Months or More, Unrealized Losses	466	803
Total, Fair Value	52,960	63,810
Total, Unrealized Losses	1,291	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	147,828	219,032
Less than 12 Months, Unrealized Losses	3,027	5,199
12 Months or More, Fair Value	15,985	16,306
12 Months or More, Unrealized Losses	979	1,033
Total, Fair Value	163,813	235,338
Total, Unrealized Losses	4,006	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	697	689
Less than 12 Months, Unrealized Losses	48	59
12 Months or More, Fair Value	0	0
12 Months or More, Unrealized Losses	0	0
Total, Fair Value	697	689
Total, Unrealized Losses	48	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	335	80
Less than 12 Months, Unrealized Losses	3	0
12 Months or More, Fair Value	5,200	4,816
12 Months or More, Unrealized Losses	670	1,049
Total, Fair Value	5,535	4,896
Total, Unrealized Losses	673	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	621	716
Less than 12 Months, Unrealized Losses	9	17
12 Months or More, Fair Value	22	22
12 Months or More, Unrealized Losses	3	3
Total, Fair Value	643	738
Total, Unrealized Losses	$ 12	$ 20