Note 6 - Investment Securities (Details) - Investment Securities with Unrealized Losses Not Recognized in Income - USD ($) $ in Thousands	Sep. 30, 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	$ 67,685	$ 81,274
Less than 12 Months, Unrealized Losses	361	254
12 Months or More, Fair Value	54,241	159,818
12 Months or More, Unrealized Losses	1,426	2,750
Total, Fair Value	121,926	241,092
Total, Unrealized Losses	1,787	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	10,201	22,696
Less than 12 Months, Unrealized Losses	71	76
12 Months or More, Fair Value	17,468	60,892
12 Months or More, Unrealized Losses	84	939
Total, Fair Value	27,669	83,588
Total, Unrealized Losses	155	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	27,192	20,746
Less than 12 Months, Unrealized Losses	159	81
12 Months or More, Fair Value	8,714	21,272
12 Months or More, Unrealized Losses	81	316
Total, Fair Value	35,906	42,018
Total, Unrealized Losses	240	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	26,332	37,451
Less than 12 Months, Unrealized Losses	74	82
12 Months or More, Fair Value	22,958	71,311
12 Months or More, Unrealized Losses	386	1,117
Total, Fair Value	49,290	108,762
Total, Unrealized Losses	460	1,199
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	3,167	0
Less than 12 Months, Unrealized Losses	1	0
12 Months or More, Fair Value	0	723
12 Months or More, Unrealized Losses	0	10
Total, Fair Value	3,167	723
Total, Unrealized Losses	1	10
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	304	76
Less than 12 Months, Unrealized Losses	11	4
12 Months or More, Fair Value	5,038	5,525
12 Months or More, Unrealized Losses	854	354
Total, Fair Value	5,342	5,601
Total, Unrealized Losses	865	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	489	305
Less than 12 Months, Unrealized Losses	45	11
12 Months or More, Fair Value	63	95
12 Months or More, Unrealized Losses	21	14
Total, Fair Value	552	400
Total, Unrealized Losses	$ 66	$ 25