Consolidated balance sheet components - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid expenses	$ 12,465	$ 4,904
Capitalized cloud computing costs, short term	808	0
Short term deposits	745	0
Other current assets	1,909	1,132
Prepaid expenses and other current assets	$ 15,927	$ 6,036

Hosting Arrangement, Service Contract, Implementation Cost, Capitalized, after Accumulated Amortization, Current

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