Note 12 - Assets and Liabilities Measured at Fair Value (Details) - USD ($) |
Mar. 31, 2016 |
Jun. 30, 2015 |
|---|---|---|
| Fair Value, Inputs, Level 1 [Member] | ||
| Cash equivalents | $ 56,628,000 | $ 84,192,000 |
| Available-for-sale Securities | ||
| Total | $ 56,628,000 | $ 84,192,000 |
| Fair Value, Inputs, Level 2 [Member] | ||
| Cash equivalents | ||
| Available-for-sale Securities | $ 2,198,000 | |
| Total | $ 2,198,000 | |
| Fair Value, Inputs, Level 3 [Member] | ||
| Cash equivalents | ||
| Available-for-sale Securities | ||
| Total | ||
| Cash equivalents | $ 56,628,000 | $ 84,192,000 |
| Available-for-sale Securities | 0 | 2,198,000 |
| Total | $ 56,628,000 | $ 86,390,000 |