Note 9 - Segment Information - Geographic Data (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
SOUTH AFRICA
Revenue, Net	$ 5,936	$ 4,968	$ 14,871	$ 15,189
% of consolidated net revenue	17.80%	17.60%	16.60%	17.50%
MEXICO
Revenue, Net	$ 5,495	$ 3,962	$ 15,600	$ 12,076
% of consolidated net revenue	16.40%	14.00%	17.40%	13.90%
CHINA
Revenue, Net	$ 3,029	$ 3,682	$ 8,646	$ 10,197
% of consolidated net revenue	9.10%	13.00%	9.60%	11.70%
BRAZIL
Revenue, Net	$ 1,850		$ 1,850
% of consolidated net revenue	5.50%		2.10%
JAPAN
Revenue, Net	$ 1,799	$ 1,306	$ 5,157	$ 3,907
% of consolidated net revenue	5.40%	4.60%	5.70%	4.50%
INDIA
Revenue, Net	$ 1,523	$ 1,385	$ 4,203	$ 5,001
% of consolidated net revenue	4.60%	4.90%	4.70%	5.70%
CANADA
Revenue, Net	$ 1,453	$ 1,368	$ 4,582	$ 4,173
% of consolidated net revenue	4.30%	4.80%	5.10%	4.80%
AUSTRALIA
Revenue, Net	$ 945	$ 829	$ 2,359	$ 3,316
% of consolidated net revenue	2.80%	2.90%	2.60%	3.80%
TURKEY
Revenue, Net	$ 76	$ 63	$ 245	$ 360
% of consolidated net revenue	0.20%	0.20%	0.30%	0.40%
International [Member]
Revenue, Net	$ 22,106	$ 17,563	$ 57,513	$ 54,219
% of consolidated net revenue	66.10%	62.00%	64.10%	62.30%
Revenue, Net	$ 33,438	$ 28,269	$ 89,781	$ 87,002