v3.26.1
Cover - shares
 6 Months Ended
May 31, 2026
Jul. 15, 2026
Document Type 10-Q  
Amendment Flag false  
Document Quarterly Report true  
Document Transition Report false  
Document Period End Date May 31, 2026  
Document Fiscal Period Focus Q2  
Document Fiscal Year Focus 2026  
Current Fiscal Year End Date --11-30  
Entity File Number 001-43169  
Entity Registrant Name ILLUMINATION ACQUISITION CORP I  
Entity Central Index Key 0002101135  
Entity Tax Identification Number 00-0000000  
Entity Incorporation, State or Country Code E9  
Entity Address, Address Line One 570 Lexington Avenue  
Entity Address, Address Line Two 40th Floor  
Entity Address, City or Town New York  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 10022  
City Area Code 646  
Local Phone Number 348-9369  
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  
Units, each consisting of one Class A ordinary share, $0.0001 par value, and one-third of one redeemable warrant [Member]    
Title of 12(b) Security Units, each consisting of one Class A ordinary share, $0.0001 par value, and one-third of one redeemable warrant  
Trading Symbol ILLUU  
Security Exchange Name NASDAQ  
Class A Ordinary shares, par value $0.0001 per share [Member]    
Title of 12(b) Security Class A Ordinary shares, par value $0.0001 per share  
Trading Symbol ILLU  
Security Exchange Name NASDAQ  
Redeemable warrants, each exercisable for Class A ordinary shares at an exercise price of $11.50 per share [Member]    
Title of 12(b) Security Redeemable warrants, each exercisable for Class A ordinary shares at an exercise price of $11.50 per share  
Trading Symbol ILLUW  
Security Exchange Name NASDAQ  
Class A ordinary shares [Member]    
Entity Common Stock, Shares Outstanding   23,625,000
Class B ordinary shares [Member]    
Entity Common Stock, Shares Outstanding   7,666,667