Revenues - Impact of ASC 606 on the Statement of Operations and Balance Sheet (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Sales and marketing	$ 19,698	$ 11,924
Prepaid expenses and other current assets	5,930	2,947	$ 2,259
Other assets	$ 1,794	809	$ 866
Cumulative transition adjustment for the new revenue standard | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Sales and marketing		66
Prepaid expenses and other current assets		(387)		$ 236
Other assets		(42)		31
Results under the prior revenue standard
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Sales and marketing		11,990
Prepaid expenses and other current assets		2,560		2,023
Other assets		$ 767		$ 835