| Shareholder Report | 12 Months Ended |
| Sep. 30, 2024 USD ($) Holding |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | SMALLCAP World Fund, Inc. |
| Entity Central Index Key | 0000858744 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Sep. 30, 2024 |
| SMALLCAP World Fund - Class A | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class A |
| Trading Symbol | SMCWX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-A |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-A |
| Expenses [Text Block] | What were the fund costs for the last year? tm Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A $ 1.04 % |
| Expenses Paid, Amount | $ 115 |
| Expense Ratio, Percent | 1.04% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class A shares gained 21.01% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-A What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class A * 14.06 % 7.15 % 7.83 % SMALLCAP World Fund — Class A (without sales charge) * 21.01 % 8.43 % 8.47 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector n assets |
| SMALLCAP World Fund - Class C | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class C |
| Trading Symbol | SCWCX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-C |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-C |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C $ 1.78 % |
| Expenses Paid, Amount | $ 196 |
| Expense Ratio, Percent | 1.78% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class C shares gained 20.11% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-C What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class C (with sales charge) * 19.11 % 7.63 % 7.81 % SMALLCAP World Fund — Class C (without sales charge) * 20.11 % 7.63 % 7.81 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to Previous * † cannot |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to Previous |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector assets |
| SMALLCAP World Fund - Class T | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class T |
| Trading Symbol | TSFFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature |
| Expenses [Text Block] | What were the fund costs for the last year? investment Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class T $ 0.75 % |
| Expenses Paid, Amount | $ 83 |
| Expense Ratio, Percent | 0.75% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class T shares gained 21.35% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years Since inception 1 SMALLCAP World Fund — Class T (with sales charge) 2 18.32 % 8.16 % 8.65 % SMALLCAP World Fund — Class T (without sales charge) 2 21.35 % 8.71 % 9.02 % MSCI ACWI IMI Index 3 30.96 % 11.87 % 10.61 % MSCI All Country World Small Cap Index 3 24.62 % 9.40 % 8.09 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. 1 2 3 |
| Performance Inception Date | Apr. 07, 2017 |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class F-1 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class F-1 |
| Trading Symbol | SCWFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-F1 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-F1 |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class F-1 $ 1.08 % |
| Expenses Paid, Amount | $ 119 |
| Expense Ratio, Percent | 1.08% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class F-1 shares gained 20.96% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-F1 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The Portfolio holdings in industrials, financials, and consu m ve ll p Geographically – US companies, where the fund had the largest exposure, saw retur ns e of |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class F-1 * 20.96 % 8.39 % 8.44 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the " Previous * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the " Previous |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class F-2 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class F-2 |
| Trading Symbol | SMCFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-F2 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-F2 |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class F-2 $ 0.77 % |
| Expenses Paid, Amount | $ 85 |
| Expense Ratio, Percent | 0.77% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class F-2 shares gained 21.32% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-F2 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class F-2 * 21.32 % 8.71 % 8.76 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class F-3 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class F-3 |
| Trading Symbol | SFCWX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-F3 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-F3 |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class F-3 $ 0.66 % |
| Expenses Paid, Amount | $ 73 |
| Expense Ratio, Percent | 0.66% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class F-3 shares gained 21.46% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-F3 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years Since inception 1 SMALLCAP World Fund — Class F-3 2 21.46 % 8.83 % 9.41 % MSCI ACWI IMI Index 3 30.96 % 11.87 % 10.76 % MSCI All Country World Small Cap Index 3 24.62 % 9.40 % 8.23 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. 1 2 3 |
| Performance Inception Date | Jan. 27, 2017 |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class 529-A | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class 529-A |
| Trading Symbol | CSPAX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529A |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-529A |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 529-A $ 1.07 % |
| Expenses Paid, Amount | $ 118 |
| Expense Ratio, Percent | 1.07% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class 529-A shares gained 20.95% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-529A What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class 529-A (with sales charge) * 16.72 % 7.62 % 8.03 % SMALLCAP World Fund — Class 529-A (without sales charge) * 20.95 % 8.39 % 8.42 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class 529-C | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class 529-C |
| Trading Symbol | CSPCX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529C |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-529C |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 529-C $ 1.81 % |
| Expenses Paid, Amount | $ 199 |
| Expense Ratio, Percent | 1.81% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class 529-C shares gained 20.08% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-529C What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class 529-C (with sales charge) * 19.08 % 7.58 % 8.00 % SMALLCAP World Fund — Class 529-C (without sales charge) * 20.08 % 7.58 % 8.00 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class 529-E | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class 529-E |
| Trading Symbol | CSPEX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529E |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-529E |
| Expenses [Text Block] | What were the fund costs for the last year? 10,000 investment Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 529-E $ 1.26 % |
| Expenses Paid, Amount | $ 139 |
| Expense Ratio, Percent | 1.26% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class 529-E shares gained 20.73% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-529E What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class 529-E * 20.73 % 8.18 % 8.20 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class 529-T | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class 529-T |
| Trading Symbol | TWSFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature |
| Expenses [Text Block] | What were the fund costs for the last year? investment Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 529-T $ 0.83 % |
| Expenses Paid, Amount | $ 92 |
| Expense Ratio, Percent | 0.83% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class 529-T shares gained 21.26% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years Since inception 1 SMALLCAP World Fund — Class 529-T (with sales charge) 2 18.22 % 8.10 % 8.60 % SMALLCAP World Fund — Class 529-T (without sales charge) 2 21.26 % 8.65 % 8.96 % MSCI ACWI IMI Index 3 30.96 % 11.87 % 10.61 % MSCI All Country World Small Cap Index 3 24.62 % 9.40 % 8.09 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. 1 2 3 |
| Performance Inception Date | Apr. 07, 2017 |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector net |
| SMALLCAP World Fund - Class 529-F-1 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class 529-F-1 |
| Trading Symbol | CSPFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529F1 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-529F1 |
| Expenses [Text Block] | What were the fund costs for the last year? 10,000 investment Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 529-F-1 $ 0.90 % |
| Expenses Paid, Amount | $ 100 |
| Expense Ratio, Percent | 0.90% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class 529-F-1 shares gained 21.17% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-529F1 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class 529-F-1 * 21.17 % 8.60 % 8.64 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class 529-F-2 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class 529-F-2 |
| Trading Symbol | FSWFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529F2 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-529F2 |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 529-F-2 $ 0.77 % |
| Expenses Paid, Amount | $ 85 |
| Expense Ratio, Percent | 0.77% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class 529-F-2 shares gained 21.32% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-529F2 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year Since inception 1 SMALLCAP World Fund — Class 529-F-2 2 21.32 % 5.31 % MSCI ACWI IMI Index 3 30.96 % 13.36 % MSCI All Country World Small Cap Index 3 24.62 % 11.27 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. 1 2 3 |
| Performance Inception Date | Oct. 30, 2020 |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class 529-F-3 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class 529-F-3 |
| Trading Symbol | FSFWX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-529F3 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-529F3 |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class 529-F-3 $ 0.71 % |
| Expenses Paid, Amount | $ 79 |
| Expense Ratio, Percent | 0.71% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class 529-F-3 shares gained 21.40% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-529F3 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year Since inception 1 SMALLCAP World Fund — Class 529-F-3 2 21.40 % 5.37 % MSCI ACWI IMI Index 3 30.96 % 13.36 % MSCI All Country World Small Cap Index 3 24.62 % 11.27 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. 1 2 3 |
| Performance Inception Date | Oct. 30, 2020 |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class R-1 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-1 |
| Trading Symbol | RSLAX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R1 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R1 |
| Expenses [Text Block] | What were the fund costs for the last year? ves Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-1 $ 1.75 % |
| Expenses Paid, Amount | $ 193 |
| Expense Ratio, Percent | 1.75% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-1 shares gained 20.15% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R1 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total return s 1 year 5 years 10 years SMALLCAP World Fund — Class R-1 * 20.15 % 7.65 % 7.67 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fu n Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector n |
| SMALLCAP World Fund - Class R-2 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-2 |
| Trading Symbol | RSLBX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R2 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R2 |
| Expenses [Text Block] | What were the fund costs for the last year? investment Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-2 $ 1.75 % |
| Expenses Paid, Amount | $ 193 |
| Expense Ratio, Percent | 1.75% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-2 shares gained 20.15% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R2 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class R-2 * 20.15 % 7.65 % 7.69 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * When † |
| No Deduction of Taxes [Text Block] | |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class R-2E | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-2E |
| Trading Symbol | RSEBX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R2E |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R2E |
| Expenses [Text Block] | What were the fund costs for the last year? investment Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-2E $ 1.46 % |
| Expenses Paid, Amount | $ 161 |
| Expense Ratio, Percent | 1.46% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-2E shares gained 20.49% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R2E What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class R-2E * 20.49 % 7.96 % 8.05 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * without † is |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class R-3 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-3 |
| Trading Symbol | RSLCX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R3 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R3 |
| Expenses [Text Block] | What were the fund costs for the last year? investment Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-3 $ 1.30 % |
| Expenses Paid, Amount | $ 143 |
| Expense Ratio, Percent | 1.30% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-3 shares gained 20.67% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R3 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class R-3 * 20.67 % 8.13 % 8.16 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * expenses † reinvested |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class R-4 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-4 |
| Trading Symbol | RSLEX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R4 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R4 |
| Expenses [Text Block] | What were the fund costs for the last year? hypothetical 10,000 Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-4 $ 1.00 % |
| Expenses Paid, Amount | $ 111 |
| Expense Ratio, Percent | 1% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-4 shares gained 21.04% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R4 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class R-4 * 21.04 % 8.45 % 8.50 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class R-5E | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-5E |
| Trading Symbol | RSLDX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R5E |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R5E |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-5E $ 0.81 % |
| Expenses Paid, Amount | $ 90 |
| Expense Ratio, Percent | 0.81% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-5E shares gained 21.29% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R5E What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years Since inception 1 SMALLCAP World Fund — Class R-5E 2 21.29 % 8.67 % 9.02 % MSCI ACWI IMI Index 3 30.96 % 11.87 % 10.34 % MSCI All Country World Small Cap Index 3 24.62 % 9.40 % 8.56 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results 1 2 3 |
| Performance Inception Date | Nov. 20, 2015 |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
| SMALLCAP World Fund - Class R-5 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-5 |
| Trading Symbol | RSLFX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R5 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R5 |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-5 $ 0.71 % |
| Expenses Paid, Amount | $ 79 |
| Expense Ratio, Percent | 0.71% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-5 shares gained 21.41% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R5 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class R-5 * 21.41 % 8.78 % 8.82 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings |
| SMALLCAP World Fund - Class R-6 | |
| Shareholder Report [Line Items] | |
| Fund Name | SMALLCAP World Fund® |
| Class Name | Class R-6 |
| Trading Symbol | RLLGX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about SMALLCAP World Fund (the "fund") |
| Shareholder Report Annual or Semi-Annual | annual shareholder report |
| Additional Information [Text Block] | You can find additional information about the fund at capitalgroup.com/mutual-fund-literature-R6 |
| Additional Information Phone Number | (800) 421-4225 |
| Additional Information Website | capitalgroup.com/mutual-fund-literature-R6 |
| Expenses [Text Block] | What were the fund costs for the last year? Share class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R-6 $ 0.66 % |
| Expenses Paid, Amount | $ 73 |
| Expense Ratio, Percent | 0.66% |
| Factors Affecting Performance [Text Block] | Management's discussion of fund performance The fund’s Class R-6 shares gained 21.46% for the year ended September 30, 2024. That result compares with a 24.62% gain for the MSCI All Country World Small Cap Index. For information on returns for additional periods, including the fund lifetime, please refer to capitalgroup.com/mutual-fund-returns-R6 What factors influenced results Global equity markets saw a strong rally over the course of the fund’s fiscal year, with easing inflation and rate cuts by the Federal Reserve restoring confidence in stocks, particularly in the United States. The market strength was particularly concentrated in mega-cap US stocks, with small-cap stocks lagging the overall market. Portfolio holdings in industrials, financials, and consumer discretionary had better returns relative to the overall portfolio. In industrials, companies that indirectly benefit from the build out in AI data centers such as Comfort Systems, as well as the reshoring trend in the US, positively contributed to results. Companies in consumer discretionary, such as Cava, TopBuild and MakeMyTrip, were additive to results as well. On the other hand, Staples and Energy shares lagged the overall portfolio. Geographically – US companies, where the fund had the largest exposure, saw returns above those of the overall portfolio. Some select emerging markets were also additive, such as India, Philippines and Turkey, while China lagged the fund. Shares domiciled in the Eurozone, the UK and Japan saw returns below that of the overall portfolio. |
| Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a predictor of its future performance. |
| Line Graph [Table Text Block] | |
| Average Annual Return [Table Text Block] | Average annual total returns 1 year 5 years 10 years SMALLCAP World Fund — Class R-6 * 21.46 % 8.84 % 8.88 % MSCI ACWI IMI Index † 30.96 % 11.87 % 9.20 % MSCI All Country World Small Cap Index † 24.62 % 9.40 % 7.81 % Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. * † |
| No Deduction of Taxes [Text Block] | The line chart and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Table Market Index Changed [Text Block] | Effective July 24, 2024, the fund's primary benchmark changed from the MSCI All Country World Small Cap Index (the "Previous Primary Benchmark") to the MSCI ACWI IMI Index, a broad-based index that represents the overall applicable securities market, as required by the SEC. The Previous Primary Benchmark provides a means to compare the fund's results to a benchmark that the investment adviser believes is more representative of the fund's investment universe. There is no change in the fund's investment strategies as a result of the benchmark change. |
| Net Assets | $ 77,077,000,000 |
| Holdings Count | Holding | 866 |
| Advisory Fees Paid, Amount | $ 428,000,000 |
| Investment Company, Portfolio Turnover | 32% |
| Additional Fund Statistics [Text Block] | Key fund statistics Fund net assets (in millions) $ Total number of portfolio holdings 866 Total advisory fees paid (in millions) $ Portfolio turnover rate 32 % |
| Holdings [Text Block] | Portfolio holdings by sector |
