Income Taxes, Components of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Assets [Abstract]
Operating loss carryforwards	$ 54,949	$ 46,203
Tax credit carryforwards	3,720	910
Other temporary differences	1,652	5,438
Deferred tax assets, gross	60,321	52,551
Less valuation allowance	(60,321)	(52,551)
Net deferred tax asset	$ 0	$ 0