Percentage of sales revenue from segments and products (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Percentage of sales revenue from segments and products
Percentage of its total third party sales revenue from a single customer in U.S. operations	30.00%	29.00%
Percentage of its total third party sales revenue from one customer in European operations	18.00%	10.00%
Percentage of its total third party sales revenue from another customer in European operations	13.00%
The European operations received approximately a percentage of its total third party sales revenue from two customers	31.00%
Percentage of its total third party sales revenue from a single customer in the Asian operations	42.00%	57.00%
One customer represented approximately Percentage of the 2013 total consolidated sales.	20.00%
One customer represented approximately Percentage of the 2012 total consolidated sales.		17.00%
Another customer represented approximately Percentage of the 2012 total consolidated sales.		16.00%
The Company's principal product, HITOX, accounted for approximately	30.00%	33.00%
Sales to customers located in the U.S. represented approximately	56.00%	48.00%
Sales to customers in Germany represented approximately	20.00%
Sales to customers in United Kingdom represented approximately		33.00%