American Funds U.S. Government Money Market Fund Class A Class 529-A Class ABLE-A Class C Class 529-C Class 529-E Class 529-T Class T Class F-1 Class F-2 Class F-3 Class 529-F-2 Class 529-F-3 Class 529-F-1 Class ABLE-F-2 Class R-1 Class R-2 Class R-3 Class R-4 Class R-5 Class R-6 Class R-2E Class R-5E Market conditions [Member] Investing in securities backed by the U.S. government [Member] Investing in repurchase agreements [Member] Interest Rate Risk [Member] Management [Member] USTREAS T-Bill Auction Ave 3 Mon (reflects no deductions for sales charges, account fees, expenses or U.S. federal income taxes) C000075895 Member C000189453 Member S000025394 Member C000164807 Member C000202065 Member C000179955 Member Market Conditions Member Investing In Repurchase Agreements Member C000075890 Member C000075892 Member index_ USTREAS_ TBill_ Auction_ Ave_3_ Mon_reflects_no_deductions_for_sales_charges_account_fees_expenses_or_ US_federal_income_taxes Member C000075900 Member C000075887 Member C000189452 Member C000075897 Member C000224559 Member C000224794 Member C000075886 Member C000148462 Member InterestRateRiskMember Investing In Securities Backed By The USGovernment Member C000075889 Member C000075898 Member C000075888 Member ManagementMember C000075891 Member C000075893 Member C000075901 Member C000075896 Member C000224560 Member