Note 3 - Investment Securities (Details) - The Amortized Cost and Estimated Fair Value of the Securities Portfolio by Contractual Maturity - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
The Amortized Cost and Estimated Fair Value of the Securities Portfolio by Contractual Maturity [Abstract]
Due in one year or less	$ 13,411
Due in one year or less	13,440
Due in one year or less	0
Due in one year or less	0
Due after one year through five years	156,691
Due after one year through five years	157,582
Due after one year through five years	0
Due after one year through five years	0
Due after five years through ten years	76,384
Due after five years through ten years	77,491
Due after five years through ten years	640
Due after five years through ten years	732
Due after ten years	15,153
Due after ten years	14,499
Due after ten years	2,971
Due after ten years	3,077
Mortgage-backed securities	314,795
Mortgage-backed securities	318,445
Mortgage-backed securities	0
Mortgage-backed securities	0
Total	576,434
Total	581,457
Total	3,611	$ 3,728
Total	$ 3,809	$ 3,923