Segment Information - Geographical Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 26,190	$ 37,610
Property and equipment, net	4,131		$ 4,728
Total Intangible Assets, Net	4,737		6,862
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	8,621	23,152
Property and equipment, net	2,699		2,974
Total Intangible Assets, Net			6,862
Foreign Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	17,569	14,458
Property and equipment, net	1,432		1,754
Other North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	152	19
Property and equipment, net	19		33
Asia Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	5,202	5,419
Property and equipment, net	1,413		1,721
CHINA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	74		163
INDIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	1,339		$ 1,558
Netherlands [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	7,704	5,223
Other EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	4,511	3,797
Europe, the Middle East and Africa [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 12,215	$ 9,020