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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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