v3.26.3
Form N-1A Cover
Sep. 18, 2026
Prospectus [Line Items]  
Document Type 485BPOS
Amendment Flag false
Registrant Name First Trust Exchange-Traded Fund
Entity Central Index Key 0001329377
Entity Investment Company Type N-1A
Document Period End Date Sep. 18, 2026
Prospectus Date Sep. 21, 2026