Acquired Fund Fees And Expenses Over Assets Acquired (underlying) fund fees and expenses Amendment Flag Amendment Flag Annual Fund Operating Expenses Table [Text Block] Annual Fund Operating Expenses [Table] Bar Chart And Performance Table Heading Bar Chart and Performance Table [Heading] Class 529-A C 000115875 [Member] Class 529-A Class 529-B C 000115876 [Member] Class 529-B Class 529-C C 000115877 [Member] Class 529-C Class 529-E C 000115878 [Member] Class 529-E Class 529-F-1 C 000115879 [Member] Class 529-F-1 Class 529-F-1 C 000115880 [Member] Class 529-F-1 Class 529-A C 000115881 [Member] Class 529-A Class 529-B C 000115882 [Member] Class 529-B Class 529-C C 000115883 [Member] Class 529-C Class 529-E C 000115884 [Member] Class 529-E Class 529-A C 000115885 [Member] Class 529-A Class 529-B C 000115886 [Member] Class 529-B Class 529-C C 000115887 [Member] Class 529-C Class 529-E C 000115888 [Member] Class 529-E Class 529-F-1 C 000115889 [Member] Class 529-F-1 Class 529-A C 000115890 [Member] Class 529-A Class 529-B C 000115891 [Member] Class 529-B Class 529-C C 000115892 [Member] Class 529-C Class 529-E C 000115893 [Member] Class 529-E Class 529-F-1 C 000115894 [Member] Class 529-F-1 Class 529-A C 000115895 [Member] Class 529-A Class 529-B C 000115896 [Member] Class 529-B Class 529-C C 000115897 [Member] Class 529-C Class 529-E C 000115898 [Member] Class 529-E Class 529-F-1 C 000115899 [Member] Class 529-F-1 Class 529-A C 000115900 [Member] Class 529-A Class 529-B C 000115901 [Member] Class 529-B Class 529-C C 000115902 [Member] Class 529-C Class 529-E C 000115903 [Member] Class 529-E Class 529-F-1 C 000115904 [Member] Class 529-F-1 Class 529-A C 000115905 [Member] Class 529-A Class 529-B C 000115906 [Member] Class 529-B Class 529-C C 000115907 [Member] Class 529-C Class 529-E C 000115908 [Member] Class 529-E Class 529-F-1 C 000115909 [Member] Class 529-F-1 Distribution And Service 12 b 1 Fees Over Assets Distribution and/or service (12b-1) fees Document Creation Date Document Creation Date Document [Domain] Prospectus Document Effective Date Document Effective Date Document Information Document [Axis] Document [Axis] Document Period End Date Document Period End Date Document Type Document Type Entity Central Index Key Central Index Key Entity [Domain] Series Entity Registrant Name Registrant Name Expense Breakpoint Discounts Expense Breakpoint Discounts [Text] Expense Breakpoint Minimum Investment Required Amount Expense Breakpoint, Minimum Investment Required [Amount] Expense Example [Abstract] Expense Example: Expense Example By Year Caption Expense Example by, Year, Caption [Text] Expense Example Heading Expense Example [Heading] Expense Example Narrative [Text Block] Expense Example Narrative [Text Block] Expense Example No Redemption [Abstract] Expense Example, No Redemption: Expense Example No Redemption By Year Caption Expense Example, No Redemption, By Year, Caption [Text] Expense Example No Redemption Table [Text Block] Expense Example, No Redemption [Table] Expense Example No Redemption Year 01 Expense Example, No Redemption, 1 Year Expense Example No Redemption Year 03 Expense Example, No Redemption, 3 Years Expense Example No Redemption Year 05 Expense Example, No Redemption, 5 Years Expense Example No Redemption Year 10 Expense Example, No Redemption, 10 Years Expense Example With Redemption Table [Text Block] Expense Example, With Redemption [Table] Expense Example Year 01 Expense Example, with Redemption, 1 Year Expense Example Year 03 Expense Example, with Redemption, 3 Years Expense Example Year 05 Expense Example, with Redemption, 5 Years Expense Example Year 10 Expense Example, with Redemption, 10 Years Expense Heading Expense [Heading] Expense Narrative [Text Block] Expense Narrative [Text Block] Expenses Over Assets Total annual fund operating expenses Fee Waiver Or Reimbursement Over Assets Fee waiver Fee waiver and/or expense reimbursement Fee waiver and/or expense reimbursement Fee waiver Fee Waiver Or Reimbursement Over Assets Date Of Termination Fee Waiver or Reimbursement over Assets, Date of Termination Legal Entity [Axis] Series [Axis] Management Fees Over Assets Management fees Maximum Account Fee Maximum annual account fee Maximum Deferred Sales Charge Over Offering Price Maximum deferred sales charge (load) (as a percentage of the amount redeemed) Maximum Sales Charge Imposed On Purchases Over Offering Price Maximum sales charge (load) imposed on purchases (as a percentage of offering price) Maximum Sales Charge On Reinvested Dividends And Distributions Over Other Maximum sales charge (load) imposed on reinvested dividends Net Expenses Over Assets Total annual fund operating expenses after fee waiver Total annual fund operating expenses after fee waiver and/or expense reimbursement Objective Heading Objective [Heading] Objective Primary [Text Block] Objective, Primary [Text Block] Operating Expenses [Abstract] Operating Expenses: Operating Expenses Caption Operating Expenses Caption [Text] Other Expenses Over Assets Other expenses Performance Narrative [Text Block] Performance Narrative [Text Block] Performance One Year Or Less Performance One Year or Less [Text] Portfolio Turnover Heading Portfolio Turnover [Heading] Portfolio Turnover [Text Block] Portfolio Turnover [Text Block] Prospectus Date ProspectusDate Prospectus Share Class [Axis] Share Class [Axis] Prospectus [Table] Prospectus: Redemption Fee Redemption or exchange fees Risk Heading Risk [Heading] Risk Lose Money Risk Lose Money [Text] Risk Narrative [Text Block] Risk Narrative [Text Block] Risk Not Insured Depository Institution Risk Not Insured Depository Institution [Text] Risk Return [Abstract] Risk/Return: Risk Return Heading Risk/Return [Heading] American Funds College 2030 FundSM S 000037534 [Member] American Funds College 2030 FundSM American Funds College 2027 FundSM S 000037535 [Member] American Funds College 2027 FundSM American Funds College 2024 FundSM S 000037536 [Member] American Funds College 2024 FundSM American Funds College 2021 FundSM S 000037537 [Member] American Funds College 2021 FundSM American Funds College 2018 FundSM S 000037538 [Member] American Funds College 2018 FundSM American Funds College 2015 FundSM S 000037539 [Member] American Funds College 2015 FundSM American Funds College Enrollment FundSM S 000037540 [Member] American Funds College Enrollment FundSM Share Class [Domain] Share Classes Shareholder Fees [Abstract] Shareholder Fees: Shareholder Fees Caption Shareholder Fees Caption [Text] Shareholder Fees Table [Text Block] Shareholder Fees [Table] Strategy Heading Strategy [Heading] Strategy Narrative [Text Block] Strategy Narrative [Text Block] American Funds College 2030 FundSM (Prospectus Summary) Summary S 000037534 [Member] American Funds College 2030 FundSM (Prospectus Summary) American Funds College 2027 FundSM (Prospectus Summary) Summary S 000037535 [Member] American Funds College 2027 FundSM (Prospectus Summary) American Funds College 2024 FundSM (Prospectus Summary) Summary S 000037536 [Member] American Funds College 2024 FundSM (Prospectus Summary) American Funds College 2021 FundSM (Prospectus Summary) Summary S 000037537 [Member] American Funds College 2021 FundSM (Prospectus Summary) American Funds College 2018 FundSM (Prospectus Summary) Summary S 000037538 [Member] American Funds College 2018 FundSM (Prospectus Summary) American Funds College 2015 FundSM (Prospectus Summary) Summary S 000037539 [Member] American Funds College 2015 FundSM (Prospectus Summary) American Funds College Enrollment FundSM (Prospectus Summary) Summary S 000037540 [Member] American Funds College Enrollment FundSM (Prospectus Summary) Trading Symbol Trading Symbol