v3.26.1
Form N-1A Cover
Oct. 31, 2025
Prospectus [Line Items]  
Document Type 497
Amendment Flag false
Registrant Name First Trust Exchange-Traded Fund IV
Entity Central Index Key 0001517936
Entity Investment Company Type N-1A
Document Creation Date Aug. 20, 2026
Document Effective Date Aug. 20, 2026
Document Period End Date Oct. 31, 2025