Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013		Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 49,508		$ 47,279
Accumulated depreciation	(41,413)		(41,141)
Total property, plant and equipment, net	8,095		6,138
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,917		2,863
Leasehold improvements | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	5 years
Leasehold improvements | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	20 years
Computer equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	36,505		36,107
Computer equipment | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	3 years
Computer equipment | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	5 years
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5,164		5,359
Machinery and equipment | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	3 years
Machinery and equipment | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life (in years)	5 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	690		870
Estimated Useful Life (in years)	5 years
Work in Progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 4,232	[1]	$ 2,080	[1]

[1] Work in progress includes internal use software development and production tooling construction in progress.