Segment Information and Enterprise-Wide Disclosure (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Segment Reporting Revenue Reconciling [Line Items]
Total sales	$ 225,275	$ 248,949	$ 423,323	$ 464,640
Inter-company sales	(66,036)	(79,143)	(119,421)	(133,279)
Net sales	159,239	169,806	303,902	331,361
Property, plant and equipment	226,943	229,793	226,943	229,793	225,393
Total assets	859,793	923,064	859,793	923,064	793,064
Percentage of net sales	100.00%	100.00%	100.00%	100.00%
Asia [Member]
Segment Reporting Revenue Reconciling [Line Items]
Total sales	145,699	150,015	273,071	281,570
Inter-company sales	(23,684)	(24,128)	(40,052)	(38,577)
Net sales	122,015	125,887	233,019	242,993
Property, plant and equipment	168,596	162,654	168,596	162,654
Total assets	517,232	512,542	517,232	512,542
North America [Member]
Segment Reporting Revenue Reconciling [Line Items]
Total sales	34,071	37,224	65,802	72,597
Inter-company sales	(15,881)	(15,878)	(31,045)	(31,210)
Net sales	18,190	21,346	34,757	41,387
Property, plant and equipment	31,127	34,459	31,127	34,459
Total assets	119,600	183,362	119,600	183,362
Europe [Member]
Segment Reporting Revenue Reconciling [Line Items]
Total sales	45,505	61,710	84,450	110,473
Inter-company sales	(26,471)	(39,137)	(48,324)	(63,492)
Net sales	19,034	22,573	36,126	46,981
Property, plant and equipment	27,220	32,680	27,220	32,680
Total assets	222,961	227,160	222,961	227,160
China [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	51,658	53,129	100,810	100,565
Percentage of net sales	32.00%	31.00%	33.00%	30.00%
Taiwan [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	31,667	36,581	63,448	74,261
Percentage of net sales	20.00%	22.00%	21.00%	23.00%
United States [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	27,926	29,928	56,196	56,457
Percentage of net sales	18.00%	18.00%	19.00%	17.00%
Korea [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	11,632	10,422	21,853	20,189
Percentage of net sales	7.00%	6.00%	7.00%	6.00%
Germany [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	6,157	7,999	12,939	17,456
Percentage of net sales	4.00%	5.00%	4.00%	5.00%
Singapore [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	6,831	6,027	11,476	11,589
Percentage of net sales	4.00%	3.00%	4.00%	4.00%
England [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	7,853	8,510	12,978	17,228
Percentage of net sales	5.00%	5.00%	4.00%	5.00%
All Others [Member]
Segment Reporting Revenue Reconciling [Line Items]
Net sales	$ 15,515	$ 17,210	$ 24,202	$ 33,616
Percentage of net sales	10.00%	10.00%	8.00%	10.00%