Note 13 - Postretirement Medical Benefits - Estimated Cost Amortized From Accumulated Other Comprehensive Income Into Net Periodic Cost (Details) - Postretirement Health Coverage [Member] $ in Thousands |
12 Months Ended |
|---|---|
|
Dec. 31, 2016
USD ($)
| |
| Unrecognized prior service cost | $ 49 |
| Total | $ 49 |