Note 9 - Defined Benefit Plans (Details) - Net Periodic Benefit Costs - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0	$ 0	$ 0
Interest cost	9	19	18	37
Expected return on plan assets	(12)	(22)	(23)	(44)
Amortization of prior service cost	0	0	0	0
Recognized net actuarial loss	3	4	7	8
Net periodic benefit cost	0	1	2	1
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	9	8	19	17
Interest cost	15	15	28	29
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	(8)	(8)	(15)	(16)
Recognized net actuarial loss	0	0	0	0
Net periodic benefit cost	$ 16	$ 15	$ 32	$ 30