Geographical Information - Schedule of Revenue and Property and Equipment by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets
Revenue	$ 92,263	$ 83,769	$ 77,436	$ 74,538	$ 72,335	$ 65,304	$ 61,120	$ 58,905	$ 328,006	$ 257,664	$ 200,225
Property and equipment, net	33,190				25,885				33,190	25,885
United States
Revenues from External Customers and Long-Lived Assets
Revenue									301,536	239,378	188,303
Property and equipment, net	29,246				23,931				29,246	23,931
International
Revenues from External Customers and Long-Lived Assets
Revenue									26,470	18,286	$ 11,922
Property and equipment, net	$ 3,944				$ 1,954				$ 3,944	$ 1,954