Income Taxes - Deferred Tax Asset / Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 8,612	$ 8,055
Capitalized research expense	1,782	823
Share based compensation	1,011	602
Research and development credits	596	636
Lease liability	43	30
Gross deferred tax assets	12,044	10,146
Less valuation allowance	(12,005)	(10,116)
Total deferred tax assets	39	30
Deferred tax liabilities:
Right of use assets	(39)	(30)
Total deferred tax liabilities	(39)	(30)
Total deferred tax assets	$ 0	$ 0