Segment and Geographical Information - Revenue by Type of Service (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 96,748	$ 78,015	$ 267,475	$ 220,274
Marketplace
Disaggregation of Revenue [Line Items]
Revenue	88,040	69,912	241,286	196,095
Managed services
Disaggregation of Revenue [Line Items]
Revenue	$ 8,708	$ 8,103	$ 26,189	$ 24,179

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details