Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 01, 2012
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	SMALLCAP World Fund®
Objective [Heading]	rr_ObjectiveHeading	Investment objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The fund's investment objective is to provide you with long-term growth of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and expenses of the fund
Expense Narrative [Text Block]	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 $25,000 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 61 of the fund's statement of additional information.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	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 [Text Block]	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 35% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	35.00%
Expense Breakpoint Discounts [Text]	rr_ExpenseBreakpointDiscounts	You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in American Funds.
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	25,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	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 [Text]	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 [Text]	rr_ExpenseExampleNoRedemptionByYearCaption	For the share classes listed below, you would pay the following if you did not redeem your shares:
Strategy [Heading]	rr_StrategyHeading	Principal investment strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Normally the fund invests at least 80% of its net assets in growth-oriented common stocks and other equity-type securities (such as preferred stocks, convertible preferred stocks and convertible bonds) of companies with small market capitalizations. The investment adviser currently defines "small market capitalization" companies to be companies with market capitalizations of $4.0 billion or less. The investment adviser has periodically re-evaluated and adjusted this definition and may continue to do so in the future. The fund may continue to hold securities of a portfolio company that subsequently appreciates above the small market capitalization threshold. Because of this, the fund may have less than 80% of its net assets in small market capitalization stocks at any given time. Under normal circumstances, the fund will invest a significant portion of its assets outside the United States, including in emerging markets. 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 companies that, in its opinion, represent good, long-term investment opportunities. The investment adviser believes that an important way to accomplish this is through fundamental analysis, which may include meeting with company executives and employees, suppliers, customers and competitors. 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 [Text Block]	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. Investors in the fund should have a long-term perspective and be able to tolerate potentially sharp declines in value. 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 growth-oriented stocks - Growth-oriented stocks may involve larger price swings and greater potential for loss than other types of investments. These risks may be even greater in the case of smaller capitalization stocks. Investing in small companies - Investing in smaller companies may pose additional risks. For example, it is often more difficult to value or dispose of small company stocks and more difficult to obtain information about smaller companies than about larger companies. In addition, the prices of these stocks may be more volatile than stocks of larger, more established companies. Investing outside the United States - Securities of issuers domiciled outside the United States, or with significant operations outside the United States, may lose value because of adverse political, social, economic or market developments in the countries or regions in which the issuer operates. These securities may also lose value due to changes in foreign currency exchange rates against the U.S. dollar and/or currencies of other countries.  Securities markets in certain countries may be more volatile and/or less liquid than those in the United States. Investments outside the United States may also be subject to different settlement and accounting practices and different regulatory, legal and reporting standards, and may be more difficult to value, than those in the United States. The risks of investing outside the United States may be heightened in connection with investments in emerging markets. Investing in emerging markets - Investing in emerging markets may involve risks in addition to and greater than those generally associated with investing in developed countries. For instance, developing countries may have less developed legal and accounting systems than those in developed countries. The governments of these countries may be less stable and more likely to impose capital controls, nationalize a company or industry, place restrictions on foreign ownership and on withdrawing sale proceeds of securities from the country, and/or impose punitive taxes that could adversely affect the prices of securities. In addition, the economies of these countries may be dependent on relatively few industries that are more susceptible to local and global changes. Securities markets in these countries can also be relatively small and have substantially lower trading volumes. As a result, securities issued in these countries may be more volatile and less liquid, and may be more difficult to value, than securities issued in countries with more developed economies and/or markets. Additionally, there may be increased settlement risks for transactions in local 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. 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 [Text]	rr_RiskLoseMoney	You may lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]	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 [Text Block]	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 broad measures of market results. This information provides some indication of the risks of investing in the fund. The Lipper Global Small-Cap Funds Average includes the fund and other funds that disclose investment objectives and/or strategies reasonably comparable to the fund's objective and/or strategies. 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 [Text]	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 broad measures of market results.
Performance Additional Market Index [Text]	rr_PerformanceAdditionalMarketIndex	Lipper Global Small-Cap Funds Average includes the fund and other funds that disclose investment objectives and/or strategies reasonably comparable to the fund's objective and/or strategies. The Consumer Price Index provides a comparison of the fund's results to inflation.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	americanfunds.com
Performance Past Does Not Indicate Future [Text]	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 [Text Block]	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 broad measures of market results.
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	(Results do not include a sales charge; if a sales charge were included, results would be lower.)
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Highest/Lowest quarterly results during this period were: Highest 28.08% (quarter ended June 30, 2009) Lowest -27.37% (quarter ended December 31, 2008) The fund's total return for the nine months ended September 30, 2012, was 18.36%.
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-favored arrangement, such as a 401(k) plan, individual retirement account (IRA) or 529 college savings plan.
Performance Table One Class of after Tax Shown [Text]	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-favored arrangement, such as a 401(k) plan, individual retirement account (IRA) or 529 college savings plan.
Caption	rr_AverageAnnualReturnCaption	Average annual total returns For the periods ended December 31, 2011 (with maximum sales charge):
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | MSCI All Country World Small Cap Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	MSCI All Country World Small Cap Index (reflects no deductions for sales charges, account fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	(11.30%)
5 Years	rr_AverageAnnualReturnYear05	0.31%
10 Years	rr_AverageAnnualReturnYear10	8.86%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 1990
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Lipper Global Small-Cap Funds Average
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Lipper Global Small-Cap Funds Average (reflects no deductions for sales charges, account fees or taxes)
1 Year	rr_AverageAnnualReturnYear01	(12.63%)
5 Years	rr_AverageAnnualReturnYear05	(1.42%)
10 Years	rr_AverageAnnualReturnYear10	6.33%
Since Inception	rr_AverageAnnualReturnSinceInception	8.67%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 1990
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Consumer Price Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Consumer Price Index
1 Year	rr_AverageAnnualReturnYear01	2.96%
5 Years	rr_AverageAnnualReturnYear05	2.26%
10 Years	rr_AverageAnnualReturnYear10	2.48%
Since Inception	rr_AverageAnnualReturnSinceInception	2.62%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 1990
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class A
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	5.75%
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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.23%
Other expenses	rr_OtherExpensesOverAssets	0.27%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.14%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	685
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	917
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,168
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,885
Annual Return 2002	rr_AnnualReturn2002	(22.25%)
Annual Return 2003	rr_AnnualReturn2003	50.40%
Annual Return 2004	rr_AnnualReturn2004	17.76%
Annual Return 2005	rr_AnnualReturn2005	16.53%
Annual Return 2006	rr_AnnualReturn2006	22.96%
Annual Return 2007	rr_AnnualReturn2007	17.15%
Annual Return 2008	rr_AnnualReturn2008	(49.40%)
Annual Return 2009	rr_AnnualReturn2009	53.49%
Annual Return 2010	rr_AnnualReturn2010	24.92%
Annual Return 2011	rr_AnnualReturn2011	(14.35%)
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund's total return for the nine months ended
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	18.36%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Highest
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	28.08%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Lowest
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(27.37%)
Label	rr_AverageAnnualReturnLabel	Share class A - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(19.27%)
5 Years	rr_AverageAnnualReturnYear05	(1.71%)
10 Years	rr_AverageAnnualReturnYear10	6.11%
Since Inception	rr_AverageAnnualReturnSinceInception	8.46%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 1990
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Share class A - After taxes on distributions
1 Year	rr_AverageAnnualReturnYear01	(19.26%)
5 Years	rr_AverageAnnualReturnYear05	(2.07%)
10 Years	rr_AverageAnnualReturnYear10	5.67%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 1990
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Share class A - After taxes on distributions and sale of fund shares
1 Year	rr_AverageAnnualReturnYear01	(12.43%)
5 Years	rr_AverageAnnualReturnYear05	(1.36%)
10 Years	rr_AverageAnnualReturnYear10	5.39%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 1990
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class B
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.26%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.90%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	693
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	998
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,228
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,028
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	193
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	598
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,028
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	2,028
Label	rr_AverageAnnualReturnLabel	Share class B - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(19.25%)
5 Years	rr_AverageAnnualReturnYear05	(1.65%)
10 Years	rr_AverageAnnualReturnYear10	6.09%
Since Inception	rr_AverageAnnualReturnSinceInception	0.39%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 15, 2000
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class C
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.29%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.93%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	296
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	605
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,040
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,250
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	196
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	605
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,040
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	2,250
Label	rr_AverageAnnualReturnLabel	Share class C - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(15.85%)
5 Years	rr_AverageAnnualReturnYear05	(1.29%)
10 Years	rr_AverageAnnualReturnYear10	5.92%
Since Inception	rr_AverageAnnualReturnSinceInception	5.32%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 15, 2001
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class F-1
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.23%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.12%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	114
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	356
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	617
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,364
Label	rr_AverageAnnualReturnLabel	Share class F-1 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.35%)
5 Years	rr_AverageAnnualReturnYear05	(0.51%)
10 Years	rr_AverageAnnualReturnYear10	6.75%
Since Inception	rr_AverageAnnualReturnSinceInception	6.09%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 15, 2001
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class F-2
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.19%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.83%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	84
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	264
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	459
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,022
Label	rr_AverageAnnualReturnLabel	Share class F-2 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.11%)
Since Inception	rr_AverageAnnualReturnSinceInception	0.57%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 01, 2008
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class 529-A
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	5.75%
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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.20%
Other expenses	rr_OtherExpensesOverAssets	0.35%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.19%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	709
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	970
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,250
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,038
Label	rr_AverageAnnualReturnLabel	Share class 529-A - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(19.32%)
5 Years	rr_AverageAnnualReturnYear05	(1.74%)
Since Inception	rr_AverageAnnualReturnSinceInception	6.78%
Inception Date	rr_AverageAnnualReturnInceptionDate	Feb. 19, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class 529-B
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.99%
Other expenses	rr_OtherExpensesOverAssets	0.38%
Total annual fund operating expenses	rr_ExpensesOverAssets	2.01%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	723
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	1,068
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,338
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,223
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	223
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	668
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,138
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	2,223
Label	rr_AverageAnnualReturnLabel	Share class 529-B - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(19.34%)
5 Years	rr_AverageAnnualReturnYear05	(1.73%)
Since Inception	rr_AverageAnnualReturnSinceInception	6.60%
Inception Date	rr_AverageAnnualReturnInceptionDate	Feb. 20, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class 529-C
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.99%
Other expenses	rr_OtherExpensesOverAssets	0.37%
Total annual fund operating expenses	rr_ExpensesOverAssets	2.00%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	322
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	665
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,132
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,420
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	222
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	665
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,132
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	2,420
Label	rr_AverageAnnualReturnLabel	Share class 529-C - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(15.91%)
5 Years	rr_AverageAnnualReturnYear05	(1.37%)
Since Inception	rr_AverageAnnualReturnSinceInception	6.45%
Inception Date	rr_AverageAnnualReturnInceptionDate	Feb. 20, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class 529-E
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other expenses	rr_OtherExpensesOverAssets	0.31%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.45%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	167
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	497
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	848
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,833
Label	rr_AverageAnnualReturnLabel	Share class 529-E - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.61%)
5 Years	rr_AverageAnnualReturnYear05	(0.86%)
Since Inception	rr_AverageAnnualReturnSinceInception	6.39%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 15, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class 529-F-1
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.35%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.99%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	121
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	354
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	604
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,313
Label	rr_AverageAnnualReturnLabel	Share class 529-F-1 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.22%)
5 Years	rr_AverageAnnualReturnYear05	(0.37%)
Since Inception	rr_AverageAnnualReturnSinceInception	10.04%
Inception Date	rr_AverageAnnualReturnInceptionDate	Sep. 17, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class R-1
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.99%
Other expenses	rr_OtherExpensesOverAssets	0.23%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.86%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	189
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	586
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,007
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,183
Label	rr_AverageAnnualReturnLabel	Share class R-1 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.99%)
5 Years	rr_AverageAnnualReturnYear05	(1.28%)
Since Inception	rr_AverageAnnualReturnSinceInception	6.93%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jun. 19, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class R-2
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.74%
Other expenses	rr_OtherExpensesOverAssets	0.51%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.89%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	192
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	595
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,022
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,214
Label	rr_AverageAnnualReturnLabel	Share class R-2 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(15.01%)
5 Years	rr_AverageAnnualReturnYear05	(1.36%)
Since Inception	rr_AverageAnnualReturnSinceInception	6.35%
Inception Date	rr_AverageAnnualReturnInceptionDate	May 31, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class R-3
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other expenses	rr_OtherExpensesOverAssets	0.28%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.42%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	145
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	451
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	778
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,706
Label	rr_AverageAnnualReturnLabel	Share class R-3 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.61%)
5 Years	rr_AverageAnnualReturnYear05	(0.85%)
Since Inception	rr_AverageAnnualReturnSinceInception	7.47%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jun. 20, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class R-4
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.19%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.08%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	110
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	343
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	594
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,314
Label	rr_AverageAnnualReturnLabel	Share class R-4 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.33%)
5 Years	rr_AverageAnnualReturnYear05	(0.50%)
Since Inception	rr_AverageAnnualReturnSinceInception	9.60%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 24, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class R-5
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.14%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.78%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	79
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	248
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	431
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	960
Label	rr_AverageAnnualReturnLabel	Share class R-5 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.08%)
5 Years	rr_AverageAnnualReturnYear05	(0.20%)
Since Inception	rr_AverageAnnualReturnSinceInception	7.15%
Inception Date	rr_AverageAnnualReturnInceptionDate	May 15, 2002
SMALLCAP WORLD FUND INC (Prospectus Summary) | SMALLCAP WORLD FUND INC | Class R-6
Risk Return [Abstract]	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	0.64%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.09%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.73%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	74
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	232
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	404
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	902
Label	rr_AverageAnnualReturnLabel	Share class R-6 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	(14.03%)
Since Inception	rr_AverageAnnualReturnSinceInception	17.44%
Inception Date	rr_AverageAnnualReturnInceptionDate	May 01, 2009

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