Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues			$ 3,797	$ 14,933	$ 16,946
Operating expenses:
Research and development			50,157	43,436	39,469
General and administrative			36,741	20,999	20,305
Truck and freight operations			24,771	9,013	7,662
Sales and marketing			4,753	3,204	3,359
Total operating expenses			116,422	76,652	70,795
Loss from operations	$ (38,710)	$ (9,460)	(112,625)	(61,719)	(53,849)
Other (expenses) income:
Interest expense			(4,096)	(4,951)	(5,407)
Interest income and other, net			(1,327)	895	2,194
Loss on issuance of equity instruments			(210,722)	0	0
Change in fair value of second lien loans			(24,387)	0	0
Change in fair value of simple agreements for future equity			(190,075)	(4,109)	0
Total other expenses, net			(472,897)	(7,739)	(3,087)
Net loss before income taxes			(585,522)	(69,458)	(56,936)
Income taxes			(3)	(1)	(9)
Net loss			(585,525)	(69,459)	(56,945)
Unrealized gains (losses) on marketable securities, net of tax			22	0	(10)
Comprehensive loss			$ (585,503)	$ (69,459)	$ (56,955)
Net loss per common share, basic (in dollars per share)			$ (6.42)	$ (1.19)	$ (0.98)
Net loss per common share, diluted (in dollars per share)			$ (6.42)	$ (1.19)	$ (0.98)
Weighted-average common shares outstanding, basic (in shares)			91,225	58,410	57,932
Weighted-average common shares outstanding, diluted (in shares)			91,225	58,410	57,932
Common stock warrants
Other (expenses) income:
Change in fair value of warrants			$ (35,018)	$ 0	$ 0
Redeemable convertible preferred stock warrants
Other (expenses) income:
Change in fair value of warrants			$ (7,272)	$ 426	$ 126