Note 3 - Summary of Investments (Details) - USD ($) | Dec. 31, 2015 | Jun. 30, 2015 |
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] | | |
Available for Sale Securities - Current | $ 9,000,000 | $ 6,300,000 |
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member] | | |
Available for Sale Securities - Current | | |
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member] | | |
Available for Sale Securities - Current | | |
Money Market Funds [Member] | | |
Available for Sale Securities - Current | $ 9,000,000 | $ 6,300,000 |
Available for Sale Securities - Total | | 6,300,000 |
Short-term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | | |
Available for Sale Securities - Current | 7,900,000 | $ 12,900,000 |
Short-term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | | |
Available for Sale Securities - Current | $ 5,100,000 | |
Short-term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | | |
Available for Sale Securities - Current | | |
Short-term Investments [Member] | | |
Available for Sale Securities - Current | $ 13,000,000 | $ 12,900,000 |
Other Long-term Investments [Member] | Fair Value, Inputs, Level 1 [Member] | | |
Available for Sale Securities - Noncurrent | 3,000,000 | |
Other Long-term Investments [Member] | Fair Value, Inputs, Level 2 [Member] | | |
Available for Sale Securities - Noncurrent | $ 2,200,000 | $ 7,900,000 |
Other Long-term Investments [Member] | Fair Value, Inputs, Level 3 [Member] | | |
Available for Sale Securities - Noncurrent | | |
Other Long-term Investments [Member] | | |
Available for Sale Securities - Noncurrent | $ 5,200,000 | $ 7,900,000 |
Fair Value, Inputs, Level 1 [Member] | | |
Available for Sale Securities - Total | 19,900,000 | 19,200,000 |
Fair Value, Inputs, Level 2 [Member] | | |
Available for Sale Securities - Total | $ 7,300,000 | $ 7,900,000 |
Fair Value, Inputs, Level 3 [Member] | | |
Available for Sale Securities - Total | | |
Available for Sale Securities - Total | $ 27,200,000 | $ 27,100,000 |