Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2025 USD ($) generator segment renewal_option	Dec. 31, 2024 USD ($) contract	Jul. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jul. 31, 2024 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Lessee, Lease, Description [Line Items]
Number of segments | segment	1
Accounts receivable from customers	$ 300,000	$ 1,500,000
Maturity date (or less)	36 months
Government assistance, number of contracts | contract		2
Received cash grants						$ 1,100,000
Options to renew (at least) | renewal_option	1
Marketing and advertising expense	$ 200,000	$ 100,000
Research and Development Service
Lessee, Lease, Description [Line Items]
Government assistance, number of generators | generator	7
Payment due (in days)	90 days
Maximum
Lessee, Lease, Description [Line Items]
Lease extension	5 years
Maximum | Research and Development Service
Lessee, Lease, Description [Line Items]
Received cash grants	$ 13,700,000			$ 16,000,000.0
Maximum | Research and Development Service, Phase II
Lessee, Lease, Description [Line Items]
Received cash grants			$ 1,500,000
Maximum | Research and Development Service, Phase I
Lessee, Lease, Description [Line Items]
Received cash grants					$ 200,000
Minimum
Lessee, Lease, Description [Line Items]
Lease extension	1 year
Supplier
Lessee, Lease, Description [Line Items]
Letter of credit							$ 7,900,000
Corporate Headquarters Lessor
Lessee, Lease, Description [Line Items]
Letter of credit	$ 700,000