v3.26.1
Cover - USD ($)
$ in Thousands
 12 Months Ended
Nov. 30, 2025
Mar. 06, 2026
May 31, 2025
Document Type 10-K/A    
Amendment Flag true    
Amendment Description This Amendment No. 1 to the Annual Report on Form 10-K (this “Amendment”) amends the Annual Report on Form 10-K of Black Hawk Acquisition Corporation (the “Company”) for the fiscal year ended November 30, 2025, as originally filed with the Securities and Exchange Commission on March 6, 2026 (the “Original Filing”).   This Amendment is being filed solely to include the Company’s Compensation Recovery (Clawback) Policy, as adopted by its Board of Directors, as Exhibit 97.1 to the Original Filing, which was inadvertently omitted.   No other changes have been made to the Original Filing. This Amendment does not reflect events occurring after the filing of the Original Filing and does not modify or update the disclosures contained in the Original Filing in any way other than as described above.    
Document Annual Report true    
Document Transition Report false    
Document Period End Date Nov. 30, 2025    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2025    
Current Fiscal Year End Date --11-30    
Entity File Number 001-41667    
Entity Registrant Name Black Hawk Acquisition Corporation    
Entity Central Index Key 0002000775    
Entity Tax Identification Number 00-0000000    
Entity Incorporation, State or Country Code E9    
Entity Address, Address Line One 4125 Blackhawk Plaza Circle    
Entity Address, Address Line Two Suite 166    
Entity Address, City or Town Danville    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 94506    
City Area Code (925)    
Local Phone Number 217-4482    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company true    
Elected Not To Use the Extended Transition Period false    
Entity Shell Company true    
Entity Public Float     $ 73,900
Entity Common Stock, Shares Outstanding   4,153,577  
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction [Flag] false    
Units, each consisting of one ordinary share, $0.0001 par value, and one-fifth (1/5) of one right entitling the holder thereof to receive one Class A ordinary share upon the consummation of our initial business combination      
Title of 12(b) Security Units, each consisting of one ordinary share, $0.0001 par value    
Trading Symbol BKHAU    
Security Exchange Name NASDAQ    
Ordinary shares, par value $0.0001 per share      
Title of 12(b) Security Ordinary shares, par value $0.0001 per share    
Trading Symbol BKHA    
Security Exchange Name NASDAQ    
Rights, each right entitling the holder to receive one Class A ordinary share upon the consummation of our initial business combination      
Title of 12(b) Security Rights, each right entitling the holder to receive one Class A ordinary share upon the consummation of our initial business combination    
Trading Symbol BKHAR    
Security Exchange Name NASDAQ