Note 6 - Comprehensive Income (Details) - Components of Accumulated Other Comprehensive Income - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income	$ 1,908	$ 1,375
Tax effect	(648)	(468)
Accumulated other comprehensive income, net of tax	1,260	907
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income	2,284	1,975
Accumulated Other-than-Temporary Impairment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income	$ (376)	$ (600)