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Related Party Transactions - Schedule of Share-Based Payments Issued to BHES (Details) - BHES - Joint Development Agreements - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Expense Recognized
Stock issued during period, value, issued for services	$ 8,971	$ 6,807	$ 27,541	$ 17,336
Class A Common Stock
Quantity
Stock issued during period, shares, issued for services (in shares)	1,357	1,030	4,166	2,623
Expense Recognized
Stock issued during period, value, issued for services	$ 8,971	$ 6,807	$ 27,541	$ 17,336
Class B Common Stock
Quantity
Stock issued during period, shares, issued for services (in shares)	1,357	1,030	4,166	2,623
Expense Recognized
Stock issued during period, value, issued for services	$ 0	$ 0	$ 0	$ 0

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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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