Segment and Geographical Information - Revenue by Geographic Area Based on Billing Address of Freelancers and Clients (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 96,748	$ 78,015	$ 267,475	$ 220,274
Freelancers
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	58,743	47,869	163,021	138,645
Freelancers | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	15,832	12,870	44,129	36,999
Freelancers | India
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	8,796	7,046	24,148	20,444
Freelancers | Philippines
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	5,995	5,077	16,436	14,488
Freelancers | Rest of world
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	28,120	22,876	78,308	66,714
Clients
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	38,005	30,146	104,454	81,629
Clients | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	28,861	23,502	76,174	62,607
Clients | Rest of world
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 9,144	$ 6,644	$ 28,280	$ 19,022