16. Sales by Product (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Product Information [Line Items]
Total Sales	$ 8,998	$ 10,036	$ 9,850	$ 9,572	$ 7,993	$ 8,988	$ 9,963	$ 10,115	$ 38,456	$ 37,059
Revenues from sales by product, percentage									100.00%	100.00%
Variance [Member]
Product Information [Line Items]
Total Sales									$ 1,397
Revenues from sales by product, percentage									4.00%
ALUPREM [Member]
Product Information [Line Items]
Total Sales									$ 18,516	$ 13,319
Revenues from sales by product, percentage									44.00%	36.00%
ALUPREM [Member] | Variance [Member]
Product Information [Line Items]
Total Sales									$ 3,483
Revenues from sales by product, percentage									26.00%
HITOX [Member]
Product Information [Line Items]
Total Sales									$ 8,006	$ 10,392
Revenues from sales by product, percentage									21.00%	28.00%
HITOX [Member] | Variance [Member]
Product Information [Line Items]
Total Sales									$ (2,386)
Revenues from sales by product, percentage									(23.00%)
BARTEX / BARYPREM [Member]
Product Information [Line Items]
Total Sales									$ 8,217	$ 8,417
Revenues from sales by product, percentage									21.00%	23.00%
BARTEX / BARYPREM [Member] | Variance [Member]
Product Information [Line Items]
Total Sales									$ (200)
Revenues from sales by product, percentage									(2.00%)
HALTEX / OPTILOAD [Member]
Product Information [Line Items]
Total Sales									$ 4,364	$ 3,462
Revenues from sales by product, percentage									11.00%	9.00%
HALTEX / OPTILOAD [Member] | Variance [Member]
Product Information [Line Items]
Total Sales									$ 902
Revenues from sales by product, percentage									26.00%
TIOPREM [Member]
Product Information [Line Items]
Total Sales									$ 742	$ 718
Revenues from sales by product, percentage									2.00%	2.00%
TIOPREM [Member] | Variance [Member]
Product Information [Line Items]
Total Sales									$ 24
Revenues from sales by product, percentage									3.00%
SR [Member]
Product Information [Line Items]
Total Sales									$ 0	$ 14
Revenues from sales by product, percentage									0.00%	0.00%
SR [Member] | Variance [Member]
Product Information [Line Items]
Total Sales									$ (14)
Revenues from sales by product, percentage									(100.00%)
OTHER [Member]
Product Information [Line Items]
Total Sales									$ 325	$ 737
Revenues from sales by product, percentage									1.00%	2.00%
OTHER [Member] | Variance [Member]
Product Information [Line Items]
Total Sales									$ (412)
Revenues from sales by product, percentage									(56.00%)