Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Nov. 01, 2011
U.S. Government Securities Fund (Prospectus Summary) | U.S. Government Securities Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return, Heading	rr_RiskReturnHeading	U.S. Government Securities Fund(SM)
Investment Objective, Heading	rr_ObjectiveHeading	Investment objective
investment Objective, Primary	rr_ObjectivePrimaryTextBlock	The fund's investment objective is to provide a high level of current income consistent with prudent investment risk and preservation of capital.
Expense, Heading	rr_ExpenseHeading	Fees and expenses of the fund
Expense, Narrative	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Funds. More information about these and other discounts is available from your financial professional and in the "Sales charge reductions and waivers" section on page 26 of the prospectus and on page 57 of the fund's statement of additional information.
Shareholder Fees, Caption	rr_ShareholderFeesCaption	Shareholder fees (fees paid directly from your investment)
Operating Expenses, Caption	rr_OperatingExpensesCaption	Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover, Heading	rr_PortfolioTurnoverHeading	Portfolio turnover
Portfolio Turnover	rr_PortfolioTurnoverTextBlock	The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund's investment results. During the most recent fiscal year, the fund's portfolio turnover rate was 212% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	212.00%
Expense Breakpoint, Discounts	rr_ExpenseBreakpointDiscounts	You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Funds.
Expense Breakpoint, Minimum Investment Required Amount	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 100,000
Expense Example, Heading	rr_ExpenseExampleHeading	Example
Expense Example, Narrative	rr_ExpenseExampleNarrativeTextBlock	This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same.
Expense Example, By Year, Caption	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example, No Redemption, By Year, Caption	rr_ExpenseExampleNoRedemptionByYearCaption	For the share classes listed below, you would pay the following if you did not redeem your shares:
Investment Strategy, Heading	rr_StrategyHeading	Principal investment strategies
Investment Strategy, Narrative	rr_StrategyNarrativeTextBlock	Normally, the fund's assets will be invested primarily in securities that are guaranteed or sponsored by the U.S. government, including bonds and other debt securities. The fund may also invest in mortgage-backed securities issued by federal agencies and instrumentalities that are not backed by the full faith and credit of the U.S. government. The fund invests in debt securities with a wide range of maturities. The investment adviser uses a system of multiple portfolio counselors in managing the fund's assets. Under this approach, the portfolio of the fund is divided into segments managed by individual counselors who decide how their respective segments will be invested. The fund relies on the professional judgment of its investment adviser to make decisions about the fund's portfolio investments. The basic investment philosophy of the investment adviser is to seek to invest in attractively valued securities that, in its opinion, represent good, long-term investment opportunities. The investment adviser believes that an important way to accomplish this is by analyzing various factors, which may include the credit strength of the issuer, prices of similar securities issued by comparable issuers, anticipated changes in interest rates, general market conditions and other factors pertinent to the particular security being evaluated. Securities may be sold when the investment adviser believes that they no longer represent relatively attractive investment opportunities.
Risk, Heading	rr_RiskHeading	Principal risks
Risk, Narrative	rr_RiskNarrativeTextBlock	This section describes the principal risks associated with the fund's principal investment strategies. You may lose money by investing in the fund. The likelihood of loss may be greater if you invest for a shorter period of time. Market conditions - The prices of, and the income generated by, the securities held by the fund may decline due to market conditions and other factors, including those directly involving the issuers of securities held by the fund. Investing in bonds - Rising interest rates will generally cause the prices of bonds and other debt securities to fall. Longer maturity debt securities may be subject to greater price fluctuations than shorter maturity debt securities. Investing in securities backed by the U.S. government - Securities backed by the U.S. Treasury or the full faith and credit of the U.S. government are guaranteed only as to the timely payment of interest and principal when held to maturity. Accordingly, the current market values for these securities will fluctuate with changes in interest rates. Securities issued by government-sponsored entities and federal agencies and instrumentalities that are not backed by the full faith and credit of the U.S. government are neither issued nor guaranteed by the U.S. government. Investing in mortgage-related securities - Mortgage-related securities are subject to prepayment risk, as well as the risks associated with investing in debt securities in general. If interest rates fall and the loans underlying these securities are prepaid faster than expected, the fund may have to reinvest the prepaid principal in lower yielding securities, thus reducing the fund's income. Conversely, if interest rates increase and the loans underlying the securities are prepaid more slowly than expected, the expected duration of the securities may be extended. This reduces the potential for the fund to invest the principal in higher yielding securities. Management - The investment adviser to the fund actively manages the fund's investments. Consequently, the fund is subject to the risk that the methods and analyses employed by the investment adviser in this process may not produce the desired results. This could cause the fund to lose value or its investment results to lag relevant benchmarks or other funds with similar objectives. It is important to note that neither your investment in the fund nor the fund's yield is guaranteed by the U.S. government. Your investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency, entity or person. You should consider how this fund fits into your overall investment program.
Risk, Lose Money	rr_RiskLoseMoney	You may lose money by investing in the fund.
Risk, Not Insured Depository Institution	rr_RiskNotInsuredDepositoryInstitution	Your investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency, entity or person.
Bar Chart and Performance Table, Heading	rr_BarChartAndPerformanceTableHeading	Investment results
Performance, Narrative	rr_PerformanceNarrativeTextBlock	The following bar chart shows how the fund's investment results have varied from year to year, and the following table shows how the fund's average annual total returns for various periods compare with different broad measures of market results. This information provides some indication of the risks of investing in the fund. The fund has selected the Barclays Capital U.S. Government/Mortgage-Backed Securities Index to replace the Citigroup Treasury/Government Sponsored/Mortgage Index as its broad-based securiites market index. The fund's investment adviser believes that the Barclays Capital U.S. Government/Mortgage-Backed Securities Index better reflects the market sectors and securities in which the fund primarily invests than the Citigroup Treasury/Government Sponsored/Mortgage Index. Lipper General U.S. Government Funds Average includes the fund and other funds that disclose investment objectives and/or strategies reasonably comparable to the fund's objective. The Consumer Price Index provides a comparison of the fund's results to inflation. Past investment results (before and after taxes) are not predictive of future investment results. Updated information on the fund's investment results can be obtained by visiting americanfunds.com.
Performance, Information Illustrates Variability of Returns	rr_PerformanceInformationIllustratesVariabilityOfReturns	The following bar chart shows how the fund's investment results have varied from year to year, and the following table shows how the fund's average annual total returns for various periods compare with different broad measures of market results.
Performance, Additional Market Index	rr_PerformanceAdditionalMarketIndex	Lipper General U.S. Government Funds Average includes the fund and other funds that disclose investment objectives and/or strategies reasonably comparable to the fund's objective. The Consumer Price Index provides a comparison of the fund's results to inflation.
Performance, Availability Website Address	rr_PerformanceAvailabilityWebSiteAddress	americanfunds.com
Performance, Past Does Not Indicate Future	rr_PerformancePastDoesNotIndicateFuture	Past investment results (before and after taxes) are not predictive of future investment results.
Bar Chart, Heading	rr_BarChartHeading	Calendar year total returns for Class A shares (Results do not include a sales charge; if a sales charge were included, results would be lower.)
Bar Chart, Narrative	rr_BarChartNarrativeTextBlock	The following bar chart shows how the fund's investment results have varied from year to year, and the following table shows how the fund's average annual total returns for various periods compare with different broad measures of market results.
Bar Chart, Does Not Reflect Sales Loads	rr_BarChartDoesNotReflectSalesLoads	(Results do not include a sales charge; if a sales charge were included, results would be lower.)
Bar Chart, Closing	rr_BarChartClosingTextBlock	Highest/Lowest quarterly results during this period were: Highest 5.34% (quarter ended December 31, 2008) Lowest -2.00% (quarter ended June 30, 2004) The fund’s total return for the nine months ended September 30, 2011, was 6.98%.
Performance Table, Market Index Changed	rr_PerformanceTableMarketIndexChanged	The fund has selected the Barclays Capital U.S. Government/Mortgage-Backed Securities Index to replace the Citigroup Treasury/Government Sponsored/Mortgage Index as its broad-based securiites market index.
Performance Table, Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the highest individual federal income tax rates in effect during each year of the periods shown and do not reflect the impact of state and local taxes.
Performance Table, Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns depend on your individual tax situation and likely will differ from the results shown above. In addition, after-tax returns are not relevant if you hold your fund shares through a tax-deferred arrangement, such as a 401(k) plan, individual retirement account (IRA) or 529 college savings plan.
Performance Table, One Class of after Tax Shown	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown only for Class A shares; after-tax returns for other share classes will vary.
Performance Table, Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are shown only for Class A shares; after-tax returns for other share classes will vary. After-tax returns are calculated using the highest individual federal income tax rates in effect during each year of the periods shown and do not reflect the impact of state and local taxes. Your actual after-tax returns depend on your individual tax situation and likely will differ from the results shown above. In addition, after-tax returns are not relevant if you hold your fund shares through a tax-deferred arrangement, such as a 401(k) plan, individual retirement account (IRA) or 529 college savings plan.
Performance Table, Footnotes	rr_PerformanceTableFootnotesTextBlock	Class A annualized 30-day yield at August 31, 2011: 1.66% (For current yield information, please call American FundsLine® at 800/325-3590.)
Average Annual Returns, Caption	rr_AverageAnnualReturnCaption	Average annual total returns For the periods ended December 31, 2010 (with maximum sales charge):
U.S. Government Securities Fund (Prospectus Summary) | U.S. Government Securities Fund | Class A
Risk/Return:	rr_RiskReturnAbstract
Year to Date Return, Label	rr_YearToDateReturnLabel	The fund’s total return for the nine months
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2011
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	6.98%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Highest
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2008
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	5.34%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Lowest
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Jun. 30, 2004
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(2.00%)
Thirty Day Yield, Caption	rr_ThirtyDayYieldCaption	Class A annualized 30-day yield at August 31, 2011:
Thirty Day Yield, Phone Number	rr_ThirtyDayYieldPhone	800/325-3590
Thirty Day Yield	rr_ThirtyDayYield	1.66%
U.S. Government Securities Fund | Barclays Capital U.S. Government/Mortgage-Backed Securities Index
Risk/Return:	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Barclays Capital U.S. Government/Mortgage-Backed Securities Index (reflects no deductions for sales charges, account fees, expenses or taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.41%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	5.88%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	5.64%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	7.52%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 17, 1985
U.S. Government Securities Fund | Citigroup Treasury/Govt. Sponsored/Mortgage Index
Risk/Return:	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Citigroup Treasury/Govt. Sponsored/Mortgage Index (reflects no deductions for sales charges, account fees, expenses or taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.59%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	5.93%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	5.69%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	7.55%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 17, 1985
U.S. Government Securities Fund | Lipper General U.S. Government Funds Average
Risk/Return:	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Lipper General U.S. Government Funds Average (reflects no deductions for sales charges, account fees or taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.92%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.68%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	4.66%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	6.36%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 17, 1985
U.S. Government Securities Fund | Consumer Price Index
Risk/Return:	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Consumer Price Index
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	1.50%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	2.18%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	2.34%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	2.82%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 17, 1985
U.S. Government Securities Fund | Class A
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	3.75%
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%	[1]
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.24%
Other expenses	rr_OtherExpensesOverAssets	0.14%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.61%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	435
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	563
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	703
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,109
Annual Return 2001	rr_AnnualReturn2001	6.41%
Annual Return 2002	rr_AnnualReturn2002	9.02%
Annual Return 2003	rr_AnnualReturn2003	1.91%
Annual Return 2004	rr_AnnualReturn2004	2.88%
Annual Return 2005	rr_AnnualReturn2005	2.27%
Annual Return 2006	rr_AnnualReturn2006	3.15%
Annual Return 2007	rr_AnnualReturn2007	6.67%
Annual Return 2008	rr_AnnualReturn2008	7.73%
Annual Return 2009	rr_AnnualReturn2009	2.16%
Annual Return 2010	rr_AnnualReturn2010	5.69%
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class A - Before taxes
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	1.76%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.25%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	4.36%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	6.35%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 17, 1985
U.S. Government Securities Fund | Class A | After Taxes on Distributions
Risk/Return:	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class A - After taxes on distributions
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	0.07%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	2.78%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	2.90%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 17, 1985
U.S. Government Securities Fund | Class A | After Taxes on Distributions and Sales
Risk/Return:	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class A - After taxes on distributions and sale of fund shares
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	1.50%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	2.79%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	2.86%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 17, 1985
U.S. Government Securities Fund | Class B
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	5.00%
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.14%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.37%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	639
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	834
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	950
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,438
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	139
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	434
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	750
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	1,438
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class B (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	(0.08%)
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	3.96%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10	4.17%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.81%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 15, 2000
U.S. Government Securities Fund | Class C
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.19%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.42%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	245
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	449
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	776
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,702
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	145
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	449
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	776
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	1,702
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class C (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	3.85%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.25%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	3.78%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 15, 2001
U.S. Government Securities Fund | Class F-1
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.15%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.63%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	64
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	202
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	351
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	786
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class F-1 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.66%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	5.09%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.59%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 15, 2001
U.S. Government Securities Fund | Class F-2
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.15%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.38%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	39
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	122
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	213
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	480
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class F-2 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.94%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	6.19%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 07, 2008
U.S. Government Securities Fund | Class 529-A
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	3.75%
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%	[1]
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Maximum annual account fee (529 share classes only)	rr_MaximumAccountFee	10
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.22%
Other expenses	rr_OtherExpensesOverAssets	0.24%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.69%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	463
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	627
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	803
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,307
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class 529-A (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	1.69%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.20%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.00%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Feb. 20, 2002
U.S. Government Securities Fund | Class 529-B
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	5.00%
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Maximum annual account fee (529 share classes only)	rr_MaximumAccountFee	10
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.25%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.48%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	670
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	907
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	1,065
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,656
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	170
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	507
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	865
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	1,656
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class 529-B (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	(0.20%)
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	3.83%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	3.66%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Feb. 20, 2002
U.S. Government Securities Fund | Class 529-C
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Maximum annual account fee (529 share classes only)	rr_MaximumAccountFee	10
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.99%
Other expenses	rr_OtherExpensesOverAssets	0.26%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.48%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	270
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	507
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	865
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,868
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	170
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	507
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	865
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	1,868
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class 529-C (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	3.78%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.18%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	3.59%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Feb. 19, 2002
U.S. Government Securities Fund | Class 529-E
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Maximum annual account fee (529 share classes only)	rr_MaximumAccountFee	10
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.49%
Other expenses	rr_OtherExpensesOverAssets	0.25%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.97%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	119
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	348
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	594
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,293
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class 529-E (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.32%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.71%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.26%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 07, 2002
U.S. Government Securities Fund | Class 529-F-1
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Maximum annual account fee (529 share classes only)	rr_MaximumAccountFee	10
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.25%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.48%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	69
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	194
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	328
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	710
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class 529-F-1 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.84%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	5.23%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.16%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Oct. 11, 2002
U.S. Government Securities Fund | Class R-1
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.18%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.41%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	144
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	446
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	771
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,691
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class R-1 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	4.84%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.23%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	3.65%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Jun. 13, 2002
U.S. Government Securities Fund | Class R-2
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.75%
Other expenses	rr_OtherExpensesOverAssets	0.43%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.41%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	144
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	446
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	771
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,691
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class R-2 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	4.85%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.27%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	3.72%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	May 31, 2002
U.S. Government Securities Fund | Class R-3
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other expenses	rr_OtherExpensesOverAssets	0.25%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.98%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	100
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	312
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	542
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	1,201
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class R-3 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.29%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	4.70%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.14%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	Jun. 06, 2002
U.S. Government Securities Fund | Class R-4
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.16%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.64%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	65
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	205
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	357
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	798
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class R-4 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.65%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	5.06%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.53%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	May 28, 2002
U.S. Government Securities Fund | Class R-5
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.11%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.34%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	35
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	109
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	191
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	431
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class R-5 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.97%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	5.38%
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.91%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	May 15, 2002
U.S. Government Securities Fund | Class R-6
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFee	none
Management fees	rr_ManagementFeesOverAssets	0.23%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.06%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.29%
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	30
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	93
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	163
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	$ 368
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Share class R-6 (before taxes)
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	6.02%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05
Average Annual Returns, 10 Years	rr_AverageAnnualReturnYear10
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	4.71%
Average Annual Returns, Inception Date	rr_AverageAnnualReturnInceptionDate	May 01, 2009

[1] A contingent deferred sales charge of 1.00% applies on certain redemptions made within one year following purchases of $1 million or more made without an initial sales charge.