Note 3 - Revenue - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation Of Revenue [Line Items]
Gross sales	$ 139,130	$ 103,711
Single-Use Products [Member]
Disaggregation Of Revenue [Line Items]
Gross sales	71,901
Multi-Use Products [Member]
Disaggregation Of Revenue [Line Items]
Gross sales	62,679
Service Revenue [Member]
Disaggregation Of Revenue [Line Items]
Gross sales	$ 4,550