Income Taxes - Components of the company’s current and deferred tax assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Operating loss carryforwards	$ 13,657	$ 7,082
Research credit carryforwards	1,233	434
Operating lease liability	285	439
Accrued expenses and other	3,050	1,779
Total deferred tax assets	18,225	9,734
Deferred tax liabilities:
Operating lease right-of-use asset	(270)	(422)
Depreciation & amortization	(311)	(326)
Total deferred tax liabilities	(581)	(748)
Valuation allowance	16,085	8,104
Net deferred tax assets	$ 1,559	$ 882