Segment Information and Information about Geographic Area (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments (in segment) | segment			1
Revenues	$ 59,490	$ 50,987	$ 167,913	$ 145,701
Property and equipment, net	51,281		51,281		$ 39,401
United States
Segment Reporting Information [Line Items]
Revenues	42,287	35,965	118,786	102,850
Property and equipment, net	37,615		37,615		30,733
Other
Segment Reporting Information [Line Items]
Revenues	17,203	$ 15,022	49,127	$ 42,851
Property and equipment, net	$ 13,666		$ 13,666		$ 8,668