Geographic Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 248,484	$ 125,295	$ 83,830
Property and equipment, net	25,403	15,196
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	172,188	73,277	51,461
Property and equipment, net	21,782	12,680
Other international
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	55,941	35,971	21,779
Property and equipment, net	3,621	2,516
UNITED KINGDOM
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 20,355	$ 16,047	$ 10,590