Reverse Recapitalization - Transaction Expenses (Details) - Terrestrial Energy Development, Inc - HCM II Acquisition Corp	12 Months Ended
Dec. 31, 2025 USD ($)
Terrestrial Transaction expenses
Professional fees	$ 14,324,981
Legal expenses	7,980,748
Total transaction costs	$ 22,305,729

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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