v3.25.2
Form N-1A Cover
Sep. 10, 2025
Prospectus [Line Items]  
Document Type 485BPOS
Amendment Flag false
Registrant Name CAPITAL GROUP COMPLETION FUND SERIES
Entity Central Index Key 0002020645
Entity Investment Company Type N-1A
Document Period End Date Sep. 10, 2025
Prospectus Date Sep. 11, 2025