Note 6 - Investment Securities (Details) - Investment Securities with Unrealized Losses Not Recognized in Income (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Note 6 - Investment Securities (Details) - Investment Securities with Unrealized Losses Not Recognized in Income [Line Items]
Less than 12 Months, Fair Value	$ 115,592	$ 81,274
Less than 12 Months, Unrealized Losses	587	254
12 Months or More, Fair Value	56,619	159,818
12 Months or More, Unrealized Losses	1,285	2,750
Total, Fair Value	172,211	241,092
Total, Unrealized Losses	1,872	3,004
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	50,220	22,696
Less than 12 Months, Unrealized Losses	184	76
12 Months or More, Fair Value	19,720	60,892
12 Months or More, Unrealized Losses	183	939
Total, Fair Value	69,940	83,588
Total, Unrealized Losses	367	1,015
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	25,634	20,746
Less than 12 Months, Unrealized Losses	175	81
12 Months or More, Fair Value	8,103	21,272
12 Months or More, Unrealized Losses	107	316
Total, Fair Value	33,737	42,018
Total, Unrealized Losses	282	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	39,182	37,451
Less than 12 Months, Unrealized Losses	160	82
12 Months or More, Fair Value	23,363	71,311
12 Months or More, Unrealized Losses	460	1,117
Total, Fair Value	62,545	108,762
Total, Unrealized Losses	620	1,199
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	133	76
Less than 12 Months, Unrealized Losses	3	4
12 Months or More, Fair Value	5,363	5,525
12 Months or More, Unrealized Losses	523	354
Total, Fair Value	5,496	5,601
Total, Unrealized Losses	526	358
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	423	305
Less than 12 Months, Unrealized Losses	65	11
12 Months or More, Fair Value	70	95
12 Months or More, Unrealized Losses	12	14
Total, Fair Value	493	400
Total, Unrealized Losses	77	25
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
Less than 12 Months, Unrealized Losses		0
12 Months or More, Fair Value		723
12 Months or More, Unrealized Losses		10
Total, Fair Value		723
Total, Unrealized Losses		$ 10