v3.26.1
Cover - shares
 3 Months Ended
Mar. 31, 2026
May 14, 2026
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Transition Report false  
Entity File Number 001-42173  
Document Period End Date Mar. 31, 2026  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q1  
Entity Registrant Name Launch One Acquisition Corp.  
Current Fiscal Year End Date --12-31  
Entity Central Index Key 0002015502  
Amendment Flag false  
Entity Incorporation, State or Country Code E9  
Entity Tax Identification Number 98-1781481  
Entity Address, Address Line One 180 Grand Avenue  
Entity Address, Address Line Two Suite 1530  
Entity Address, City or Town Oakland  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 94612  
City Area Code (510)  
Local Phone Number 692-9600  
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  
Units, each consisting of one Class A ordinary share and one-half of one redeemable warrant    
Document Information [Line Items]    
Title of 12(b) Security Units, each consisting of one Class A Ordinary Share and one-half of one redeemable Warrant  
Trading Symbol LPAAU  
Security Exchange Name NASDAQ  
Class A ordinary shares, par value $0.0001 per share    
Document Information [Line Items]    
Title of 12(b) Security Class A Ordinary Shares, par value $0.0001 per share  
Trading Symbol LPAA  
Security Exchange Name NASDAQ  
Redeemable Warrants, each whole Warrant exercisable for one Class A Ordinary Share at an exercise price of $11.50 per share    
Document Information [Line Items]    
Title of 12(b) Security Redeemable Warrants, each whole Warrant exercisable for one Class A Ordinary Share at an exercise price of $11.50 per share  
Trading Symbol LPAAW  
Security Exchange Name NASDAQ  
Class A Ordinary Shares    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   23,000,000
Class B Ordinary Shares    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   5,750,000