Commitments and Contingencies - Maturities of operating lease liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Maturities of operating lease liabilities:
Remainder of 2024	$ 422
2025	641
Total lease payments	1,063
Less: imputed interest	(74)
Total lease liabilities	989	$ 1,400
Current operating lease liabilities	$ 778
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued Liabilities, Current	Accrued Liabilities, Current
Non-current operating lease liabilities	$ 211
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Accrued Liabilities, Noncurrent	Other Accrued Liabilities, Noncurrent