v3.26.1
Cover
Apr. 29, 2026
Document Type 8-K
Amendment Flag false
Document Period End Date Apr. 29, 2026
Entity File Number 001-43247
Entity Registrant Name CHURCHILL CAPITAL CORP XII
Entity Central Index Key 0002114227
Entity Tax Identification Number 98-1922580
Entity Incorporation, State or Country Code E9
Entity Address, Address Line One 640 Fifth Avenue
Entity Address, Address Line Two 14th Floor
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 380-7500
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company true
Elected Not To Use the Extended Transition Period false
Units, each consisting of one Class A ordinary share and one-tenth of one redeemable warrant  
Title of 12(b) Security Units, each consisting of one Class A ordinary share and one-tenth of one redeemable warrant
Trading Symbol CXIIU
Security Exchange Name NASDAQ
Class A ordinary shares, par value $0.0001 per share  
Title of 12(b) Security Class A ordinary shares, par value $0.0001 per share
Trading Symbol CXII
Security Exchange Name NASDAQ
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 CXIIW
Security Exchange Name NASDAQ