Document and Entity Information |
Sep. 30, 2025 |
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| Document and Entity Information [Abstract] | |
| Document Type | S-1 |
| Entity Registrant Name | Black Spade Acquisition III Co |
| Entity Filer Category | Non-accelerated Filer |
| Entity Small Business | true |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Entity Central Index Key | 0002087087 |
| Amendment Flag | false |
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- Definition Boolean flag that is true when the XBRL content amends previously-filed or accepted submission. No definition available.
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- Definition Cover page. No definition available.
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- Definition The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'. No definition available.
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- Definition A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate if registrant meets the emerging growth company criteria. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate whether the registrant is one of the following: Large Accelerated Filer, Accelerated Filer, Non-accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicates that the company is a Smaller Reporting Company (SRC). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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