Segment Reporting Geographic Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues	$ 57,918		$ 67,480	$ 62,339	$ 59,857	$ 60,007		$ 58,169	$ 59,171	$ 59,733	$ 247,594		$ 237,080		$ 250,112
Long-Lived Assets (1)	60,453	[1]				57,779	[1]				60,453	[1]	57,779	[1]	60,692	[1]
United States of America
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											55,574		62,667		66,267
Long-Lived Assets (1)	50,125					48,432					50,125		48,432		51,715
Other North American Countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											176		144		193
Long-Lived Assets (1)	0					0					0		0		0
Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											23,324		28,050		36,896
Long-Lived Assets (1)	9					16					9		16		24
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											25,114		23,503		22,507
Long-Lived Assets (1)	3,093					2,956					3,093		2,956		3,492
Singapore
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											31,899		26,353		23,899
Long-Lived Assets (1)	9					9					9		9		8
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											16,073		15,873		16,183
Long-Lived Assets (1)	1,684					2,424					1,684		2,424		1,417
Hong Kong
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											43,060		33,881		37,300
Long-Lived Assets (1)	60					86					60		86		215
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											16,582		14,686		14,329
Long-Lived Assets (1)	2					23					2		23		1
Other Asian Countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											1,377		1,259		1,284
Long-Lived Assets (1)	5,447					3,727					5,447		3,727		3,717
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Net Revenues											34,415		30,664		31,254
Long-Lived Assets (1)	$ 24					$ 106					$ 24		$ 106		$ 103

[1] Long-lived assets consist of property, plant and equipment.