Segment Reporting and Geographic Information (Details) - Company`s reportable segments (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Revenues	$ 10,341	$ 11,579
(Loss) income from operations	(2,714)	(1,476)
Operating Segments [Member] | Heavy Duty Diesel Systems [Member]
Segment Reporting Information [Line Items]
Revenues	4,152	6,275
(Loss) income from operations	(378)	296
Operating Segments [Member] | Catalyst [Member]
Segment Reporting Information [Line Items]
Revenues	6,811	5,811
(Loss) income from operations	(558)	222
Operating Segments [Member] | Corporate Segment [Member]
Segment Reporting Information [Line Items]
(Loss) income from operations	(1,710)	(1,974)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(622)	(507)
(Loss) income from operations	$ (68)	$ (20)