Description of Business and Summary of Significant Accounting Policies - Other income (expense), net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Description of Business and Summary of Significant Accounting Policies
Gain (loss) on remeasurement of debt		$ 488		$ (924)
Gain (loss) on remeasurement of legacy preferred stock warrant liability		785		(1,214)
Other, net	$ 316	145	$ 225	88
Total other income (expense), net	$ 316	$ 1,418	$ 225	$ (2,050)