Note 12 - Pension Plan - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Pension Plan [Member]
Service cost	$ 16	$ 17	$ 49	$ 51
Interest cost	17	15	50	46
Expected return on plan assets	(16)	(17)	(49)	(51)
Amortization of net actuarial loss and prior service cost	1	2	5	5
Net periodic pension cost	18	17	55	51
Service cost	4	5	12	15
Interest cost	4	3	10	9
Amortization of net actuarial loss and prior service cost	(1)	(2)	(5)	(5)
Net periodic pension cost	$ 8	$ 8	$ 22	$ 24