After Taxes on Distributions After Taxes on Distributions and Sale of Fund Shares Average Annual Returns, Inception Date Average Annual Returns, Since Inception Average Annual Returns, 10 Years Average Annual Returns, 1 Year Average Annual Returns, 5 Years Risk/Return Summary [Abstract] index_Bloomberg_US_Aggregate_Index_reflects_no_deductions_for_sales_charges_account_fees_expenses_or_US_federal_income_taxes Bloomberg U.S. Aggregate Index (reflects no deductions for sales charges, account fees, expenses or U.S. federal income taxes) index_Bloomberg_US_Aggregate_15_Years_Index_reflects_no_deductions_for_sales_charges_account_fees_expenses_or_US_federal_income_taxes Bloomberg U.S. Aggregate 1–5 Years Index (reflects no deductions for sales charges, account fees, expenses or U.S. federal income taxes) index_SP_500_Index_reflects_no_deductions_for_sales_charges_account_fees_expenses_or_US_federal_income_taxes S&P 500 Index (reflects no deductions for sales charges, account fees, expenses or U.S. federal income taxes) Risk/Return: Prospectus: Document Type Document Period End Date Entity Registrant Name Entity Central Index Key Entity Inv Company Type Amendment Flag Document Creation Date Document Effective Date Trading Symbol Prospectus Date American Funds College 2042 Fund Class 529-F-2 (American Funds College 2042 Fund) Class 529-F-2 Class 529-T (American Funds College 2042 Fund) Class 529-T Class 529-F-3 (American Funds College 2042 Fund) Class 529-F-3 Class 529-A (American Funds College 2042 Fund) Class 529-A Class 529-E (American Funds College 2042 Fund) Class 529-E Class 529-C (American Funds College 2042 Fund) Class 529-C Class 529-F-1 (American Funds College 2042 Fund) Class 529-F-1 Maximum sales charge (load) imposed on purchases (as a percentage of offering price) Maximum deferred sales charge (load) (as a percentage of the amount redeemed) Maximum sales charge (load) imposed on reinvested dividends Redemption or exchange fees Management fees Distribution and/or service (12b-1) fees Other expenses Acquired (underlying) fund fees and expenses Total annual fund operating expenses Expense Example, with Redemption, 1 Year 1 year Expense Example, No Redemption, 1 Year 1 year Expense Example, with Redemption, 3 Years 3 years Expense Example, No Redemption, 3 Years 3 years Risk Not Insured [Member] Allocation risk [Member] Fund structure [Member] Underlying fund risks [Member] Market conditions [Member] Issuer risks [Member] Investing in stocks [Member] Investing outside the United States [Member] Investing in debt instruments [Member] Investing in securities backed by the U.S. government [Member] Management [Member] All Risks [Member] American Funds College 2039 Fund Class 529-F-2 (American Funds College 2039 Fund) Class 529-F-2 Class 529-F-1 (American Funds College 2039 Fund) Class 529-F-1 Class 529-E (American Funds College 2039 Fund) Class 529-E Class 529-F-3 (American Funds College 2039 Fund) Class 529-F-3 Class 529-A (American Funds College 2039 Fund) Class 529-A Class 529-T (American Funds College 2039 Fund) Class 529-T Class 529-C (American Funds College 2039 Fund) Class 529-C Expense Example, with Redemption, 5 Years 5 years Expense Example, No Redemption, 5 Years 5 years Expense Example, with Redemption, 10 Years 10 years Expense Example, No Redemption, 10 Years 10 years Annual Return 1990 Annual Return 1991 Annual Return 1992 Annual Return 1993 Annual Return 1994 Annual Return 1995 Annual Return 1996 Annual Return 1997 Annual Return 1998 Annual Return 1999 Annual Return 2000 Annual Return 2001 Annual Return 2002 Annual Return 2003 Annual Return 2004 Annual Return 2005 Annual Return 2006 Annual Return 2007 Annual Return 2008 Annual Return 2009 Annual Return 2010 Annual Return 2011 Annual Return 2012 Annual Return 2013 Annual Return 2014 Annual Return 2015 Annual Return 2016 Annual Return 2017 Annual Return 2018 Annual Return 2019 Annual Return 2020 Annual Return 2021 Annual Return 2022 Annual Return 2023 Annual Return 2024 Annual Return 2025 Risk Lose Money [Member] American Funds College 2036 Fund Class 529-A (American Funds College 2036 Fund) Class 529-A Class 529-C (American Funds College 2036 Fund) Class 529-C Class 529-E (American Funds College 2036 Fund) Class 529-E Class 529-F-1 (American Funds College 2036 Fund) Class 529-F-1 Class 529-T (American Funds College 2036 Fund) Class 529-T Class 529-F-2 (American Funds College 2036 Fund) Class 529-F-2 Class 529-F-3 (American Funds College 2036 Fund) Class 529-F-3 American Funds College 2033 Fund Class 529-A (American Funds College 2033 Fund) Class 529-A Class 529-C (American Funds College 2033 Fund) Class 529-C Class 529-E (American Funds College 2033 Fund) Class 529-E Class 529-F-1 (American Funds College 2033 Fund) Class 529-F-1 Class 529-T (American Funds College 2033 Fund) Class 529-T Class 529-F-2 (American Funds College 2033 Fund) Class 529-F-2 Class 529-F-3 (American Funds College 2033 Fund) Class 529-F-3 Investing in mortgage-related and other asset-backed securities [Member] Investing in derivatives [Member] American Funds College 2030 Fund Class 529-A (American Funds College 2030 Fund) Class 529-A Class 529-C (American Funds College 2030 Fund) Class 529-C Class 529-E (American Funds College 2030 Fund) Class 529-E Class 529-F-1 (American Funds College 2030 Fund) Class 529-F-1 Class 529-T (American Funds College 2030 Fund) Class 529-T Class 529-F-3 (American Funds College 2030 Fund) Class 529-F-3 Class 529-F-2 (American Funds College 2030 Fund) Class 529-F-2 American Funds College 2027 Fund Class 529-F-1 (American Funds College 2027 Fund) Class 529-F-1 Class 529-A (American Funds College 2027 Fund) Class 529-A Class 529-C (American Funds College 2027 Fund) Class 529-C Class 529-E (American Funds College 2027 Fund) Class 529-E Class 529-T (American Funds College 2027 Fund) Class 529-T Class 529-F-2 (American Funds College 2027 Fund) Class 529-F-2 Class 529-F-3 (American Funds College 2027 Fund) Class 529-F-3 American Funds College 2024 Fund Class 529-A (American Funds College 2024 Fund) Class 529-A Class 529-C (American Funds College 2024 Fund) Class 529-C Class 529-E (American Funds College 2024 Fund) Class 529-E Class 529-F-1 (American Funds College 2024 Fund) Class 529-F-1 Class 529-T (American Funds College 2024 Fund) Class 529-T Class 529-F-2 (American Funds College 2024 Fund) Class 529-F-2 Class 529-F-3 (American Funds College 2024 Fund) Class 529-F-3 American Funds College Enrollment Fund Class 529-A (American Funds College Enrollment Fund) Class 529-A Class 529-C (American Funds College Enrollment Fund) Class 529-C Class 529-E (American Funds College Enrollment Fund) Class 529-E Class 529-F-1 (American Funds College Enrollment Fund) Class 529-F-1 Class 529-T (American Funds College Enrollment Fund) Class 529-T Class 529-F-3 (American Funds College Enrollment Fund) Class 529-F-3 Class 529-F-2 (American Funds College Enrollment Fund) Class 529-F-2 Supplement to Prospectus [Text Block] Supplement to Prospectus [Text Block] Risk/Return [Heading] Risk/Return [Heading] Objective [Heading] Objective [Heading] Objective, Primary [Text Block] Objective, Primary [Text Block] Objective, Secondary [Text Block] Objective, Secondary [Text Block] Expense [Heading] Expense [Heading] Expense Narrative [Text Block] Expense Narrative [Text Block] Shareholder Fees Caption [Text] Shareholder Fees Caption [Text] Shareholder Fees Column [Text] Shareholder Fees Column [Text] Maximum Cumulative Sales Charge (as a percentage of Offering Price) Maximum Cumulative Sales Charge (as a percentage of Offering Price) Maximum Cumulative Sales Charge (as a percentage) Maximum Cumulative Sales Charge (as a percentage) Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) Maximum Deferred Sales Charge (as a percentage of Offering Price) Maximum Deferred Sales Charge (as a percentage) Maximum Deferred Sales Charge (as a percentage) Maximum Sales Charge on Reinvested Dividends and Distributions (as a percentage) Redemption Fee (as a percentage of Amount Redeemed) Redemption Fee Redemption Fee Exchange Fee (as a percentage of Amount Redeemed) Exchange Fee (as a percentage of Amount Redeemed) Exchange Fee Exchange Fee Maximum Account Fee (as a percentage of Assets) Maximum Account Fee (as a percentage of Assets) Maximum Account Fee Maximum Account Fee Shareholder Fee, Other Shareholder Fee, Other Operating Expenses Caption [Text] Operating Expenses Caption [Text] Operating Expenses Column [Text] Operating Expenses Column [Text] Management Fees (as a percentage of Assets) Distribution and Service (12b-1) Fees Distribution or Similar (Non 12b-1) Fees Distribution or Similar (Non 12b-1) Fees Component1 Other Expenses Component1 Other Expenses Component2 Other Expenses Component2 Other Expenses Component3 Other Expenses Component3 Other Expenses Other Expenses (as a percentage of Assets): Acquired Fund Fees and Expenses Expenses (as a percentage of Assets) Fee Waiver or Reimbursement Fee Waiver or Reimbursement Net Expenses (as a percentage of Assets) Net Expenses (as a percentage of Assets) Fee Waiver or Reimbursement over Assets, Date of Termination Fee Waiver or Reimbursement over Assets, Date of Termination Portfolio Turnover [Heading] Portfolio Turnover [Heading] Portfolio Turnover [Text Block] Portfolio Turnover [Text Block] Portfolio Turnover, Rate Portfolio Turnover, Rate Expense Footnotes [Text Block] Expense Footnotes [Text Block] Expenses Deferred Charges [Text Block] Expenses Deferred Charges [Text Block] Expenses Range of Exchange Fees [Text Block] Expenses Range of Exchange Fees [Text Block] Expense Breakpoint Discounts [Text] Expense Breakpoint Discounts [Text] Expense Breakpoint, Minimum Investment Required [Amount] Expense Breakpoint, Minimum Investment Required [Amount] Expenses Represent Both Master and Feeder [Text] Expenses Represent Both Master and Feeder [Text] Expenses Explanation of Nonrecurring Account Fee [Text] Expenses Explanation of Nonrecurring Account Fee [Text] Other Expenses, New Fund, Based on Estimates [Text] Other Expenses, New Fund, Based on Estimates [Text] Acquired Fund Fees and Expenses, Based on Estimates [Text] Acquired Fund Fees and Expenses, Based on Estimates [Text] Expenses Other Expenses Had Extraordinary Expenses Been Included [Text] Expenses Other Expenses Had Extraordinary Expenses Been Included [Text] Expenses Restated to Reflect Current [Text] Expenses Restated to Reflect Current [Text] Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] Expense Example [Heading] Expense Example [Heading] Expense Example by Year [Heading] Expense Example by Year [Heading] Expense Example Narrative [Text Block] Expense Example Narrative [Text Block] Expense Example by, Year, Caption [Text] Expense Example by, Year, Caption [Text] Expense Example, By Year, Column [Text] Expense Example, By Year, Column [Text] Expense Example, No Redemption Narrative [Text Block] Expense Example, No Redemption Narrative [Text Block] Expense Example, No Redemption, By Year, Caption [Text] Expense Example, No Redemption, By Year, Caption [Text] Expense Example, No Redemption, By Year, Column [Text] Expense Example, No Redemption, By Year, Column [Text] Expense Example Footnotes [Text Block] Expense Example Footnotes [Text Block] Expense Example Closing [Text Block] Expense Example Closing [Text Block] Strategy [Heading] Strategy [Heading] Strategy Narrative [Text Block] Strategy Narrative [Text Block] Strategy Portfolio Concentration [Text] Strategy Portfolio Concentration [Text] Risk [Heading] Risk [Heading] Risk Narrative [Text Block] (Deprecated 2023-01-31) Risk Narrative [Text Block] (Deprecated 2023-01-31) Risk [Text Block] Risk [Text Block] Risk Footnotes [Text Block] Risk Footnotes [Text Block] Risk Closing [Text Block] Risk Closing [Text Block] Risk Lose Money [Text] (Deprecated 2023-01-31) Risk Lose Money [Text] (Deprecated 2023-01-31) Risk Nondiversified Status [Text] (Deprecated 2023-01-31) Risk Nondiversified Status [Text] (Deprecated 2023-01-31) Risk Not Insured Depository Institution [Text] (Deprecated 2023-01-31) Risk Not Insured Depository Institution [Text] (Deprecated 2023-01-31) Risk Money Market Fund May Impose Fees or Suspend Sales [Text] (Deprecated 2023-01-31) Risk Money Market Fund May Impose Fees or Suspend Sales [Text] (Deprecated 2023-01-31) Risk Money Market Fund May Not Preserve Dollar [Text] (Deprecated 2023-01-31) Risk Money Market Fund May Not Preserve Dollar [Text] (Deprecated 2023-01-31) Risk Money Market Fund Price Fluctuates [Text] (Deprecated 2023-01-31) Risk Money Market Fund Price Fluctuates [Text] (Deprecated 2023-01-31) Risk Money Market Fund Sponsor May Not Provide Support [Text] (Deprecated 2023-01-31) Risk Money Market Fund Sponsor May Not Provide Support [Text] (Deprecated 2023-01-31) Risk Not Insured [Text] (Deprecated 2023-01-31) Risk Not Insured [Text] (Deprecated 2023-01-31) Risk Caption Risk Caption Risk Column [Text] Risk Column [Text] Risk [Text] (Deprecated 2023-01-31) Risk [Text] (Deprecated 2023-01-31) Bar Chart and Performance Table [Heading] Bar Chart and Performance Table [Heading] Performance Narrative [Text Block] Performance Narrative [Text Block] Performance Information Illustrates Variability of Returns [Text] Performance Information Illustrates Variability of Returns [Text] Performance One Year or Less [Text] Performance One Year or Less [Text] Performance Additional Market Index [Text] Performance Additional Market Index [Text] Performance Availability Phone [Text] Performance Availability Phone [Text] Performance Availability Website Address [Text] Performance Availability Website Address [Text] Performance Past Does Not Indicate Future [Text] Performance Past Does Not Indicate Future [Text] Bar Chart [Heading] Bar Chart [Heading] Bar Chart Narrative [Text Block] Bar Chart Narrative [Text Block] Bar Chart Does Not Reflect Sales Loads [Text] Bar Chart Does Not Reflect Sales Loads [Text] Annual Return Caption [Text] Annual Return Caption [Text] Annual Return, Column [Text] Annual Return, Column [Text] Annual Return, Inception Date Annual Return, Inception Date Annual Return 1990 Annual Return 1991 Annual Return 1992 Annual Return 1993 Annual Return 1994 Annual Return 1995 Annual Return 1996 Annual Return 1997 Annual Return 1998 Annual Return 1999 Annual Return 2000 Annual Return 2001 Annual Return 2002 Annual Return 2003 Annual Return 2004 Annual Return 2005 Annual Return 2006 Annual Return 2007 Annual Return 2008 Annual Return 2009 Annual Return 2010 Annual Return 2011 Annual Return 2012 Annual Return 2013 Annual Return 2014 Annual Return 2015 Annual Return 2016 Annual Return 2017 Annual Return 2018 Annual Return 2019 Annual Return 2020 Annual Return 2021 Annual Return 2022 Annual Return 2023 Annual Return 2024 Annual Return 2025 Bar Chart Footnotes [Text Block] Bar Chart Footnotes [Text Block] Bar Chart Closing [Text Block] Bar Chart Closing [Text Block] Bar Chart, Reason Selected Class Different from Immediately Preceding Period [Text] Bar Chart, Reason Selected Class Different from Immediately Preceding Period [Text] Bar Chart, Returns for Class Not Offered in Prospectus [Text] Bar Chart, Returns for Class Not Offered in Prospectus [Text] Year to Date Return, Label Year to Date Return, Label Bar Chart, Year to Date Return, Date Bar Chart, Year to Date Return, Date Bar Chart, Year to Date Return Bar Chart, Year to Date Return Highest Quarterly Return, Label Highest Quarterly Return, Label Highest Quarterly Return, Date Highest Quarterly Return, Date Highest Quarterly Return Highest Quarterly Return Lowest Quarterly Return, Label Lowest Quarterly Return, Label Lowest Quarterly Return, Date Lowest Quarterly Return, Date Lowest Quarterly Return Lowest Quarterly Return Performance Table Heading Performance Table Heading Performance Table Does Reflect Sales Loads Performance Table Does Reflect Sales Loads Performance Table Market Index Changed Performance Table Market Index Changed Index No Deduction for Fees, Expenses, Taxes [Text] Index No Deduction for Fees, Expenses, Taxes [Text] Performance Table Uses Highest Federal Rate Performance Table Uses Highest Federal Rate Performance Table Not Relevant to Tax Deferred Performance Table Not Relevant to Tax Deferred Performance Table One Class of after Tax Shown [Text] Performance Table One Class of after Tax Shown [Text] Performance Table Explanation after Tax Higher Performance Table Explanation after Tax Higher Performance Table Narrative Performance Table Narrative Performance Table Footnotes, Reason Performance Information for Class Different from Immediately Preceding Period [Text] Performance Table Footnotes, Reason Performance Information for Class Different from Immediately Preceding Period [Text] Performance Table Footnotes Performance Table Footnotes Performance Table Closing [Text Block] Performance Table Closing [Text Block] Average Annual Return, Caption Average Annual Return, Caption Average Annual Return, Column Name Average Annual Return, Column Name Label Label 1 Year 5 Years 10 Years Since Inception Inception Date Money Market Seven Day Yield, Caption [Text] Money Market Seven Day Yield, Caption [Text] Money Market Seven Day Yield Column [Text] Money Market Seven Day Yield Column [Text] Money Market Seven Day Yield Phone Money Market Seven Day Yield Phone Money Market Seven Day Yield Money Market Seven Day Yield Money Market Seven Day Tax Equivalent Yield Money Market Seven Day Tax Equivalent Yield Thirty Day Yield Caption Thirty Day Yield Caption Thirty Day Yield Column [Text] Thirty Day Yield Column [Text] Thirty Day Yield Phone Thirty Day Yield Phone Thirty Day Yield Thirty Day Yield Thirty Day Tax Equivalent Yield Thirty Day Tax Equivalent Yield Shareholder Fees [Table] Annual Fund Operating Expenses [Table] Expense Example, With Redemption [Table] Expense Example, No Redemption [Table] Bar Chart [Table] Performance [Table] Share Class [Axis] Performance Measure [Axis] Document Information, Document [Axis] Legal Entity [Axis] After Taxes on Distributions After Taxes on Distributions and Sales Risk [Axis] Investing Outside The United States Member All Risks [Member] Investing In Debt Instruments Member Investing In Stocks Member Investing In Securities Backed By The USGovernment Member Underlying Fund Risks Member Issuer Risks Member Market Conditions Member Investing In Derivatives Member Investing In Mortgagerelated And Other Assetbacked Securities Member Risk Lose Money [Member] Fund Structure Member Management Member Allocation Risk Member Risk Not Insured [Member]