Note 17 - Acquisition Activity - Unaudited Pro Forma Condensed Consolidated Statement of Operations (Details) - Imugen and Immunetics [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Total revenues	$ 92,860	$ 75,622
Net loss	$ (21,840)	$ (25,281)
Net loss per share—basic and diluted (in dollars per share)	$ (0.98)	$ (1.16)
Weighted average shares outstanding—basic and diluted (in shares)	22,353,713	21,781,933