Segment and Geographical Information - Property, Plant and Equipment, Net Based On Geographical Information (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	$ 63,729	$ 49,029
India
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	37,139	23,362
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	14,829	10,809
Philippines
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	9,031	11,900
Rest of World
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	$ 2,730	$ 2,958