Note 9 - Fuel Derivatives (Details Textual) $ in Millions |
3 Months Ended |
|---|---|
|
Sep. 30, 2016
USD ($)
bbl
| |
| Diesel Fuel Future Contracts [Member] | |
| Derivative, Nonmonetary Notional Amount, Volume | 2,520,000 |
| Derivative, Nonmonetary Notional Amount, Volume per Month | 252,000 |
| Derivative Nonmonetary, Percentage of Monthly Projected Fuel Requirements | 7.50% |
| Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred | $ | $ (0.1) |