Other Financial Information - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid insurance	$ 2,037	$ 728
Engineering and consulting costs	70	2,137
Supplier advances	8,899	0
Other	1,341	0
Total prepaid expenses	12,347	2,865
Restricted cash	64,222	0	$ 0
Other	9,465	286
Total other assets, current	$ 73,687	$ 286

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