Note 6 - Prepaid Expenses and Other Current Assets (Details) - Prepaid Expenses and Other Current Assets - USD ($) $ in Thousands |
May. 31, 2015 |
May. 31, 2014 |
|---|---|---|
| Prepaid Expenses and Other Current Assets [Abstract] | ||
| Income tax prepayments | $ 4,267 | $ 5,736 |
| Prepaid expenses | 3,942 | 5,677 |
| Other receivables | 2,952 | 1,169 |
| Prepaid expenses and other current assets | $ 11,161 | $ 12,582 |