Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands		9 Months Ended
	Dec. 08, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Cash and Cash Equivalents, at Carrying Value		$ 98,279	$ 98,894	$ 138,909	$ 74,103
Cash and Cash Equivalents, Period Increase (Decrease)		$ (40,630)	24,791
Number of Years Cash is Sufficient to Fund Operations		1 year
Return of Estimated Interest Payment for Noncontrolling Interest		$ 21
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment		$ 1,480		$ 838
EXINI Diagnostics AB [Member]
Payments to Noncontrolling Interests	$ 368