Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 46,462	$ 35,729
Research and development credits	7,288	5,223
Stock-based compensation	848	322
Operating lease liabilities	382	661
Other	73	140
Total gross deferred tax assets	55,053	42,075
Less: Valuation allowance	(54,697)	(41,451)
Total deferred tax assets	356	624
Operating lease right-of-use assets	(356)	(624)
Total deferred tax liabilities	$ (356)	$ (624)