Note 3 - Investment Securities (Details) - Income Earned on Securities (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Non-taxable:
Total	$ 4,717	$ 3,428	$ 14,032	$ 9,349
Held-to-Maturity Securities [Member]
Taxable:
Taxable Investment Income	1,440	818	4,167	2,281
Non-taxable:
Non-taxable Investment Income	2,647	2,066	7,900	5,450
Available-for-sale Securities [Member]
Taxable:
Taxable Investment Income	603	540	1,882	1,605
Non-taxable:
Non-taxable Investment Income	$ 27	$ 4	$ 83	$ 13