Note 13 - Postretirement Medical Benefits (Details) - Estimated Cost Amortized from Accumulated Other Comprehensive Income into Net Periodic Cost - Postretirement Medical Benefits [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Note 13 - Postretirement Medical Benefits (Details) - Estimated Cost Amortized from Accumulated Other Comprehensive Income into Net Periodic Cost [Line Items]
Unrecognized prior service cost	$ 50
Total	$ 50