Geographical Information (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 53,565	$ 44,991
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	48,640	39,412
India
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	3,766	3,969
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 1,159	$ 1,610