v3.26.1
Document and Entity Information - shares
2 Months Ended
Jun. 30, 2026
Aug. 10, 2026
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2026  
Document Transition Report false  
Entity File Number 001-43385  
Entity Registrant Name MERIDIAN3 INDUSTRIALS ACQUISITION CORP  
Entity Incorporation, State or Country Code E9  
Entity Tax Identification Number 00-0000000  
Entity Address, Address Line One 1330 Avenue of the Americas  
Entity Address, Adress Line Two Suite 23A  
Entity Address, City or Town New York  
Entity Address State Or Province NY  
Entity Address, Postal Zip Code 10019  
City Area Code 212  
Local Phone Number 653-0982  
Entity Current Reporting Status No  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Shell Company true  
Inception Date May 11, 2026  
Entity Central Index Key 0002136530  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q2  
Units, each consisting of one Class A ordinary share and one-half of one redeemable warrant    
Title of 12(b) Security Units, each consisting of one Class A ordinary share and one-half of one redeemable warrant  
Trading Symbol MIACU  
Security Exchange Name NASDAQ  
Class A ordinary shares    
Title of 12(b) Security Class A ordinary shares, par value $0.0001 per share  
Trading Symbol MIAC  
Security Exchange Name NASDAQ  
Entity Common Stock, Shares Outstanding   20,125,000
Warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 per share    
Title of 12(b) Security Warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 per share  
Trading Symbol MIACW  
Security Exchange Name NASDAQ  
Class B ordinary shares    
Entity Common Stock, Shares Outstanding   5,031,250