American Funds U.S. Small & Mid Cap Equity Fund Class A Class 529-A Class C Class 529-C Class 529-E Class F-3 Class F-2 Class F-1 Class 529-F-3 Class 529-F-2 Class R-5E Class R-5 Class R-4 Class R-3 Class R-2E Class R-2 Class R-1 Class R-6 Market conditions [Member] Issuer risks [Member] Investing in small and mid-capitalization companies [Member] Liquidity risk [Member] Management [Member] Russell 3000 Index (reflects no deductions for sales charges, account fees, expenses or U.S. federal income taxes) Russell 2500 Index (reflects no deductions for sales charges, account fees, expenses or U.S. federal income taxes) Russell Midcap Index (reflects no deductions for sales charges, account fees, expenses or U.S. federal income taxes) C000253810 Member index_ Russell_2500_ Index_reflects_no_deductions_for_sales_charges_account_fees_expenses_or_ US_federal_income_taxes Member C000253807 Member C000253817 Member Market Conditions Member Investing In Small And Midcapitalization Companies Member C000253825 Member C000253815 Member C000253822 Member C000253812 Member Liquidity Risk Member Issuer Risks Member C000253811 Member S000087820 Member C000253824 Member C000253808 Member index_ Russell_ Midcap_ Index_reflects_no_deductions_for_sales_charges_account_fees_expenses_or_ US_federal_income_taxes Member C000253818 Member C000253814 Member ManagementMember C000253819 Member C000253813 Member C000253809 Member index_ Russell_3000_ Index_reflects_no_deductions_for_sales_charges_account_fees_expenses_or_ US_federal_income_taxes Member C000253816 Member C000253821 Member C000253826 Member