Fair Value of Financial Instruments - Schedule of Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Investments	$ 32,332
Liabilities:
Warrant liability	14,563	$ 46
Recurring | Level 1
Assets:
Investments	32,332	0
Recurring | Level 1 | Public Warrants
Liabilities:
Warrant liability	14,167	0
Recurring | Level 2 | Private Warrants
Liabilities:
Warrant liability	396	0
Recurring | Level 3 | Legacy Heliogen preferred stock warrants
Liabilities:
Warrant liability	$ 0	$ 46