Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement [Abstract]
Revenues		$ 7,264	$ 2,773	$ 9,658	$ 3,735
Cost of sales (exclusive of items shown separately below)		2,202	1,112	4,189	2,019
Gross profit		5,062	1,661	5,469	1,716
Operating expenses:
Engineering services		11,999	5,784	23,716	10,731
General and administrative costs		13,075	9,157	24,718	14,693
Research and development costs		9,145	9,589	17,426	10,603
Depreciation and amortization		1,185	567	2,285	1,182
Total operating expenses		35,404	25,097	68,145	37,209
Nonoperating Income (Expense) [Abstract]
Gain (loss) on remeasurement of warrant liabilities		23,049	(41,677)	17,567	(41,677)
Other expense, net		(679)	0	(664)	(28)
Total other income (expense), net		22,370	(41,677)	16,903	(41,705)
Loss before income tax expense		(7,972)	(65,113)	(45,773)	(77,198)
Income tax expense		96	56	198	57
Net loss before allocation to noncontrolling interest		(8,068)	(65,169)	(45,971)	(77,255)
Net loss attributable to noncontrolling interest		(5,144)	(45,191)	(32,326)	(45,697)
Net loss attributable to common stockholders		$ (2,924)	$ (19,978)	$ (13,645)	$ (31,558)
Net income (loss) per share of common stock attributable to common shareholders
Earnings per share of Class A common stock - Basic	[1]	$ (0.06)	$ (0.39)	$ (0.26)	$ (0.39)
Earnings per share of Class A common stock - Diluted	[1]	$ (0.06)	$ (0.39)	$ (0.26)	$ (0.39)
Weighted average shares used in computing net income (loss) per share of common stock
Weighted-average shares of Class A common stock outstanding - basic	[1]	51,868,658	51,729,704	51,814,888	51,729,704
Weighted-average shares of Class A common stock outstanding - diluted	[1]	51,868,658	51,729,704	51,814,888	51,729,704

[1] (1) Earnings per share information excludes earnings for the periods prior to the Business Combination, as it resulted in values that would not be meaningful to the users of these condensed consolidated financial statements. Refer to Note 14 for further information.