Segment Information - Geographical Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 68,178	$ 75,487
Property and equipment, net	17,698		17,713
Total Intangible Assets, Net	66,763		70,284
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	26,050	28,761
Property and equipment, net	9,017		8,572
Total Intangible Assets, Net	65,553		68,903
Other North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	652	800
Property and equipment, net	829		953
Total Intangible Assets, Net	168		211
CHINA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	6,745	10,540
Property and equipment, net	4,462		4,685
JAPAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	8,560	6,633
INDIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	3,066		3,110
Other Asia Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	11,217	9,305
Property and equipment, net	297		358
Asia Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	26,522	26,478
Property and equipment, net	7,825		8,153
Europe, the Middle East and Africa [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	14,954	19,448
Property and equipment, net	27		35
Total Intangible Assets, Net	1,042		1,170
Foreign Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	42,128	46,726
Property and equipment, net	8,681		9,141
Total Intangible Assets, Net	$ 1,210		$ 1,381