v3.26.3
Document And Entity Information - shares
9 Months Ended
Sep. 30, 2026
Nov. 12, 2026
Document Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Quarterly Report true  
Document Transition Report false  
Current Fiscal Year End Date --12-31  
Document Fiscal Period Focus Q3  
Document Fiscal Year Focus 2026  
Document Period End Date Sep. 30, 2026  
Entity Registrant Name JATT III ACQUISITION CORP  
Entity Central Index Key 0002145659  
Entity File Number 001-43461  
Entity Incorporation, State or Country Code E9  
Entity Tax Identification Number 00-0000000  
Entity Address, Address Line One 153 Central Avenue  
Entity Address, Address Line Two C/O 56  
Entity Address, City or Town Westfield  
Entity Address, State or Province NJ  
Entity Address, Postal Zip Code 07091  
City Area Code 201  
Local Phone Number 688-0364  
Title of 12(b) Security ordinary shares, par value $0.0001 per share  
Trading Symbol JTTT  
Security Exchange Name NASDAQ  
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  
Entity Ex Transition Period false  
Entity Shell Company true  
Entity Common Stock, Shares Outstanding   8,859,000