Note 8 - Net Loss Per Share Attributable to Common Stockholders (Tables)

6 Months Ended

Jun. 30, 2016

Notes Tables

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
	2016		2015		2016		2015
Outstanding stock options		2,234,934		1,757,959		2,234,934		1,757,959
		2,234,934		1,757,959		2,234,934		1,757,959