v3.26.1
Cover
3 Months Ended
Mar. 31, 2026
Cover [Abstract]  
Document Type S-4/A
Amendment Flag true
Amendment Description AMENDMENT NO. 2
Entity Registrant Name Hennessy Capital Investment Corp. VII
Entity Central Index Key 0001846416
Entity Tax Identification Number 99-4813262
Entity Incorporation, State or Country Code E9
Entity Address, Address Line One 195 US Hwy 50
Entity Address, Address Line Two Suite 207
Entity Address, City or Town Zephyr Cove
Entity Address, State or Province NV
Entity Address, Postal Zip Code 89448
City Area Code (775)
Local Phone Number 339-1671
Entity Filer Category Non-accelerated Filer
Entity Small Business true
Entity Emerging Growth Company true
Elected Not To Use the Extended Transition Period false