Note 7 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Note 7 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income [Line Items]
Less than 12 Months, Fair Value	$ 251,811	$ 83,590
Less than 12 Months, Unrealized Losses	7,119	498
12 Months or More, Fair Value	20,347	4,994
12 Months or More, Unrealized Losses	1,837	856
Total, Fair Value	272,158	88,584
Total, Unrealized Losses	8,956	1,354
US Government-sponsored Enterprises Debt Securities [Member]
Note 7 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income [Line Items]
Less than 12 Months, Fair Value	76,817	26,433
Less than 12 Months, Unrealized Losses	2,315	66
12 Months or More, Fair Value	0	0
12 Months or More, Unrealized Losses	0	0
Total, Fair Value	76,817	26,433
Total, Unrealized Losses	2,315	66
US States and Political Subdivisions Debt Securities [Member]
Note 7 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income [Line Items]
Less than 12 Months, Fair Value	57,780	17,199
Less than 12 Months, Unrealized Losses	1,891	174
12 Months or More, Fair Value	3,135	0
12 Months or More, Unrealized Losses	278	0
Total, Fair Value	60,915	17,199
Total, Unrealized Losses	2,169	174
Residential Mortgage Backed Securities [Member]
Note 7 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income [Line Items]
Less than 12 Months, Fair Value	116,427	39,659
Less than 12 Months, Unrealized Losses	2,894	256
12 Months or More, Fair Value	12,336	0
12 Months or More, Unrealized Losses	574	0
Total, Fair Value	128,763	39,659
Total, Unrealized Losses	3,468	256
Corporate Debt Securities [Member]
Note 7 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income [Line Items]
Less than 12 Months, Fair Value	106	0
Less than 12 Months, Unrealized Losses	2	0
12 Months or More, Fair Value	4,876	4,994
12 Months or More, Unrealized Losses	985	856
Total, Fair Value	4,982	4,994
Total, Unrealized Losses	987	856
Mutual Funds And Equity Securities [Member]
Note 7 - Investment Securities (Details) - Investment Securities With Unrealized Losses Not Recognized In Income [Line Items]
Less than 12 Months, Fair Value	681	299
Less than 12 Months, Unrealized Losses	17	2
12 Months or More, Fair Value	0	0
12 Months or More, Unrealized Losses	0	0
Total, Fair Value	681	299
Total, Unrealized Losses	$ 17	$ 2