Segment Information - Geographical Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 48,687us-gaap_Revenues	$ 43,799us-gaap_Revenues
Property and equipment, net	8,791us-gaap_PropertyPlantAndEquipmentNet		9,786us-gaap_PropertyPlantAndEquipmentNet
Total Intangible Assets, Net	39,970		43,224
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	21,172	15,706
Property and equipment, net	4,107		4,558
Total Intangible Assets, Net			43,224
Foreign Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	27,515	28,093
Property and equipment, net	4,684		5,228
Other North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	45	1,124
Property and equipment, net	542		672
Asia Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	17,185	17,495
Property and equipment, net	2,225		2,438
CHINA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	11,693	7,027
Property and equipment, net	2,217		2,427
JAPAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	2,383	7,208
INDIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	1,915		2,115
Other Asia Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	3,109	3,260
Property and equipment, net	8		11
Netherlands [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	4,362	5,039
Other EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	5,923	4,435
Property and equipment, net	2		3
Europe, the Middle East and Africa [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	10,285	9,474
Property and equipment, net	$ 1,917		$ 2,118

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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