Note 8 - Common Stock (Tables)

12 Months Ended

Dec. 31, 2015

Notes Tables

Common Stock Reserved for Future Issuance [Table Text Block]

	December 31, 2015		December 31, 2014
Stock-based compensation awards		2,419,901		1,807,349
Employee Stock Purchase Plan		297,359		140,500
Total		2,717,260		1,947,849