Segment reporting (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Net Product Sales	$ 90,845	$ 101,735	$ 323,455	$ 331,517
Net Income (Loss)	4,381	8,026	20,400	29,923
Jingzhou Henglong Automotive Parts Co Ltd [Member]
Segment Reporting Information [Line Items]
Net Product Sales	53,932	60,902	206,061	203,987
Net Income (Loss)	2,866	5,127	15,768	22,660
Shashi Jiulong Power Steering Gears Co Ltd [Member]
Segment Reporting Information [Line Items]
Net Product Sales	16,183	15,964	53,251	57,753
Net Income (Loss)	154	168	75	1,750
Shenyang Jinbei Henglong Automotive Steering System Co Ltd [Member]
Segment Reporting Information [Line Items]
Net Product Sales	7,516	8,988	24,056	32,928
Net Income (Loss)	609	998	1,418	1,760
Wuhu Henglong Automotive Steering System Co Ltd [Member]
Segment Reporting Information [Line Items]
Net Product Sales	3,925	5,941	16,096	18,345
Net Income (Loss)	(110)	(88)	(181)	(167)
Hubei Henglong Automotive System Group Co Ltd [Member]
Segment Reporting Information [Line Items]
Net Product Sales	13,818	14,425	44,463	41,708
Net Income (Loss)	1,737	1,110	5,594	44,512	[1]
Other Sector [Member]
Segment Reporting Information [Line Items]
Net Product Sales	8,656	9,887	27,433	30,210
Net Income (Loss)	(260)	252	(1,021)	1,246
Total Segments [Member]
Segment Reporting Information [Line Items]
Net Product Sales	104,030	116,107	371,360	384,931
Net Income (Loss)	4,996	7,567	21,653	71,761
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Net Product Sales	0	0	0	0
Net Income (Loss)	(996)	231	(1,538)	(1,792)
Consolidation, Eliminations [Member]
Segment Reporting Information [Line Items]
Net Product Sales	(13,185)	(14,372)	(47,905)	(53,414)
Net Income (Loss)	$ 381	$ 228	$ 285	$ (40,046)

[1] $ 40.3 million included in the balance of $ 44.5 million was income from the investment in Henglong in 2014, which has been eliminated at the consolidation level.