v3.26.1

Segment Information (Details)	4 Months Ended
Segment Information (Details)	Dec. 31, 2025 Segment
Segment Information [Line Items]
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description	The Company’s CODM has been identified as the Chief Executive Officer, who reviews the operating results for the Company as a whole to make decisions about allocating resources and assessing financial performance. Accordingly, management has determined that the Company only has one operating segment.
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	Chief Executive Officer
Number of operating segment	1
Number of reportable segment	1

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Indicates title and position of individual or name of group identified as chief operating decision maker (CODM) for segment reporting.

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Description of how chief operating decision maker (CODM) uses reported segment profit (loss) measure to assess performance and allocate resource.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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HCM IV Acquisition Corp. 10-K