Note 9 - Share-based Compensation (Details) - Summary of Status of Company's Unvested Option Shares - 6 months ended Jun. 30, 2015 - Employee Stock Option [Member] - $ / shares	Total
Note 9 - Share-based Compensation (Details) - Summary of Status of Company's Unvested Option Shares [Line Items]
Number of Shares	227,400
Weighted Average Grant Date Fair Value	$ 4.35
Options cancelled	(4,625)
Options cancelled	$ 4.14
Options vested	(32,506)
Options vested	$ 5.41
Number of Shares	190,269
Weighted Average Grant Date Fair Value	$ 4.13