Geographic Information - Summary Of Property And Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property and equipment, net	$ 62,910	$ 28,587	$ 7,901	$ 8,527
United States
Property and equipment, net		27,942	7,679	8,295
All Other Countries
Property and equipment, net		$ 645	$ 222	$ 232

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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