Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Depreciation	$ 5,479	$ 4,468	$ 3,460
Definite-lived intangible assets, net	18,706	12,389
Incentives received, reported in current and long-term deferred revenue		9,300
Deferred revenue—current	12,014	10,257
Deferred revenue—long-term	7,172	8,581
Property, plant and equipment
Property, Plant and Equipment [Line Items]
Depreciation	6,900	5,000	4,100
Internally developed software
Property, Plant and Equipment [Line Items]
Depreciation	3,200	1,500	$ 900
Definite-lived intangible assets, net	12,800	$ 8,000
Clearing firm
Property, Plant and Equipment [Line Items]
Deferred revenue—current	900
Deferred revenue—long-term	$ 7,200