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Related Party Transactions - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2025	Dec. 31, 2024
Related Party Transaction [Line Items]
Due to related parties	$ 29,459	$ 29,459	$ 6,537
Asset Purchase Commitment
Related Party Transaction [Line Items]
Unrecorded unconditional purchase obligation, weighted average share price (in dollars per share)	$ 4.00	$ 4.00
Joint Development Agreements
Related Party Transaction [Line Items]
Unrecorded unconditional purchase obligation, threshold trading days		10 days
Unrecorded unconditional purchase obligation, weighted average share price (in dollars per share)	$ 4.00	$ 4.00
BHES
Related Party Transaction [Line Items]
Gain (loss) on stock issued during period, value, issued for services		$ (17,500)
Gain (loss) on stock issued during period, value, issued for services, inception-to-date		(11,700)
BHES | Purchase Of KPEP Long Lead Time Items
Related Party Transaction [Line Items]
Related party transaction, amounts of transaction		41,500
Related Party
Related Party Transaction [Line Items]
Due to related parties	$ 29,500	29,500	$ 6,500
Related Party | BHES
Related Party Transaction [Line Items]
Due to related parties	1,300	1,300
Related party transaction, amounts of transaction	$ 1,400	$ 3,900

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