Note 11 - Revenue - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net product sales	$ 6,701	$ 5,178	$ 12,471	$ 8,993
Regenerative Medicine [Member]
Net product sales	3,978	2,985	6,157	5,089
Media [Member]
Net product sales	6,327	5,178	12,097	8,993
Distribution Service [Member]
Net product sales	2,215	1,695	5,319	2,734
Automated Thawing Products [Member]
Net product sales	374		374
Drug Discovery [Member]
Net product sales	248	263	486	640
BioBanking [Member]
Net product sales	$ 260	$ 235	$ 509	$ 530