Segment and Geographical Information - Revenue by Type of Service (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 87,531	$ 73,783	$ 170,727	$ 142,259
Marketplace
Disaggregation of Revenue [Line Items]
Revenue	78,464	65,728	153,246	126,183
Managed services
Disaggregation of Revenue [Line Items]
Revenue	$ 9,067	$ 8,055	$ 17,481	$ 16,076

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