| Label | Element | Value |
|---|---|---|
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Registrant Name | dei_EntityRegistrantName | VANGUARD SCOTTSDALE FUNDS |
| Prospectus Date | rr_ProspectusDate | Dec. 20, 2024 |
| Admiral | Vanguard Long-Term Treasury Index Fund | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Risk/Return [Heading] | rr_RiskReturnHeading | <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Long-Term Treasury Index Fund</span> |
| Objective [Heading] | rr_ObjectiveHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> |
| Objective, Primary [Text Block] | rr_ObjectivePrimaryTextBlock | The Fund seeks to track the performance of a market-weighted Treasury index with a long-term dollar-weighted average maturity. |
| Expense [Heading] | rr_ExpenseHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> |
| Expense Narrative [Text Block] | rr_ExpenseNarrativeTextBlock | The following tables describe the fees and expenses you may pay if you buy, hold, and sell Admiral Shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below. |
| Shareholder Fees Caption [Text] | rr_ShareholderFeesCaption | <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> |
| Operating Expenses Caption [Text] | rr_OperatingExpensesCaption | <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> |
| Portfolio Turnover [Heading] | rr_PortfolioTurnoverHeading | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> |
| Portfolio Turnover [Text Block] | rr_PortfolioTurnoverTextBlock | The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 21% of the average value of its portfolio. |
| Portfolio Turnover, Rate | rr_PortfolioTurnoverRate | 21.00% |
| Expense Example [Heading] | rr_ExpenseExampleHeading | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> |
| Expense Example Narrative [Text Block] | rr_ExpenseExampleNarrativeTextBlock | The following example is intended to help you compare the cost of investing in the Fund’s Admiral Shares with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you were to invest $10,000 in the Fund’s shares. This example assumes that the shares provide a return of 5% each year and that total annual fund operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you were to redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: |
| Strategy [Heading] | rr_StrategyHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> |
| Strategy Narrative [Text Block] | rr_StrategyNarrativeTextBlock | The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Long Treasury Index (the Index). This Index includes fixed income securities issued by the U.S. Treasury (not including inflation-protected bonds, floating rate securities and certain other security types), with maturities greater than 10 years. The Fund invests by sampling the Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Index in terms of key risk factors and other characteristics. All of the Fund’s investments will be selected through the sampling process, and under normal circumstances, at least 80% of the Fund’s assets will be invested in bonds included in the Index. The Fund maintains a dollar-weighted average maturity consistent with that of the Index. As of August 31, 2024, the dollar-weighted average maturity of the Index was 22.5 years. |
| Risk [Heading] | rr_RiskHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Risks</span> |
| Risk [Text Block] | rr_RiskTextBlock | • Interest rate risk, which is the chance that bond prices overall will decline because of rising interest rates. Interest rate risk should be high for the Fund because it invests primarily in long-term bonds, whose prices are more sensitive to interest rate changes than are the prices of shorter-term bonds.• Income risk, which is the chance that the Fund’s income will decline because of falling interest rates. Income risk should be low for the Fund because it invests primarily in long-term bonds.• Index-related risks. The Fund is subject to risks associated with index investing, which include passive management risk, tracking error risk, and index provider risk. Passive management risk is the chance that the Fund’s use of an indexing strategy will negatively impact the Fund’s performance. Because the Fund seeks to track the performance of its target index regardless of how that index is performing, the Fund’s performance may be lower than it would be if the Fund were actively managed. Tracking error risk is the chance that the Fund’s performance will deviate from the performance of its target index. Tracking error risk may be heightened during times of increased market volatility or under other unusual market conditions. Index provider risk is the chance that the Fund will be negatively impacted by changes or errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.• Index sampling risk, which is the chance that the securities selected for the Fund, in the aggregate, will not provide investment performance matching that of the Fund’s target index. Index sampling risk for the Fund is expected to be low. |
| Bar Chart and Performance Table [Heading] | rr_BarChartAndPerformanceTableHeading | <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> |
| Performance Narrative [Text Block] | rr_PerformanceNarrativeTextBlock | The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of the Fund’s target index and other comparative indexes, which have investment characteristics similar to those of the Fund. The Spliced Bloomberg U.S. Long Treasury Index reflects the performance of the Bloomberg U.S. Long Government Float Adjusted Index through December 11, 2017, and the Bloomberg U.S. Long Treasury Index thereafter.Keep in mind that the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance. |
| Performance Information Illustrates Variability of Returns [Text] | rr_PerformanceInformationIllustratesVariabilityOfReturns | <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of the Fund’s target index and other comparative indexes, which have investment characteristics similar to those of the Fund.</span> |
| Performance Availability Website Address [Text] | rr_PerformanceAvailabilityWebSiteAddress | <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> |
| Performance Past Does Not Indicate Future [Text] | rr_PerformancePastDoesNotIndicateFuture | <span style="font-family:Arial;font-size:9.5pt;">Keep in mind that the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> |
| Bar Chart [Heading] | rr_BarChartHeading | <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Long-Term Treasury Index Fund Admiral Shares</span><span style="font-family:Arial;font-size:5pt;font-weight:bold;position:relative;top:-3.25pt;">1</span> |
| Bar Chart Closing [Text Block] | rr_BarChartClosingTextBlock | During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were: |
| Performance Table Heading | rr_PerformanceTableHeading | <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2023</span> |
| Performance Table Uses Highest Federal Rate | rr_PerformanceTableUsesHighestFederalRate | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> |
| Performance Table Not Relevant to Tax Deferred | rr_PerformanceTableNotRelevantToTaxDeferred | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a shareholder </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> |
| Performance Table Explanation after Tax Higher | rr_PerformanceTableExplanationAfterTaxHigher | <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> |
| Performance Table Closing [Text Block] | rr_PerformanceTableClosingTextBlock | Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder. |
| Admiral | Vanguard Long-Term Treasury Index Fund | Risk Lose Money [Member] | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Risk [Text Block] | rr_RiskTextBlock | An investment in the Fund could lose money over short or long periods of time. |
| Admiral | Vanguard Long-Term Treasury Index Fund | Risk Not Insured Depository Institution [Member] | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Risk [Text Block] | rr_RiskTextBlock | An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. |
| Admiral | Vanguard Long-Term Treasury Index Fund | Admiral Shares | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| Purchase Fee | rr_MaximumCumulativeSalesChargeOverOther | none |
| Sales Charge (Load) Imposed on Purchases | rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice | none |
| Sales Charge (Load) Imposed on Reinvested Dividends | rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther | none |
| Redemption Fee | rr_RedemptionFeeOverRedemption | none |
| Account Service Fee Per Year (for certain fund account balances below $5,000,000) | rr_MaximumAccountFee | $ 25 |
| Management Fees | rr_ManagementFeesOverAssets | 0.06% |
| 12b-1 Distribution Fee | rr_DistributionAndService12b1FeesOverAssets | none |
| Other Expenses | rr_OtherExpensesOverAssets | 0.01% |
| Total Annual Fund Operating Expenses | rr_ExpensesOverAssets | 0.07% |
| 1 Year | rr_ExpenseExampleYear01 | $ 7 |
| 3 Years | rr_ExpenseExampleYear03 | 23 |
| 5 Years | rr_ExpenseExampleYear05 | 40 |
| 10 Years | rr_ExpenseExampleYear10 | $ 90 |
| Year to Date Return, Label | rr_YearToDateReturnLabel | year-to-date return |
| Bar Chart, Year to Date Return, Date | rr_BarChartYearToDateReturnDate | Sep. 30, 2024 |
| Bar Chart, Year to Date Return | rr_BarChartYearToDateReturn | 2.42% |
| Highest Quarterly Return, Label | rr_HighestQuarterlyReturnLabel | <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> |
| Highest Quarterly Return, Date | rr_BarChartHighestQuarterlyReturnDate | Mar. 31, 2020 |
| Highest Quarterly Return | rr_BarChartHighestQuarterlyReturn | 20.84% |
| Lowest Quarterly Return, Label | rr_LowestQuarterlyReturnLabel | <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> |
| Lowest Quarterly Return, Date | rr_BarChartLowestQuarterlyReturnDate | Mar. 31, 2021 |
| Lowest Quarterly Return | rr_BarChartLowestQuarterlyReturn | (13.44%) |
| 1 Year | rr_AverageAnnualReturnYear01 | 3.65% |
| 5 Years | rr_AverageAnnualReturnYear05 | (1.36%) |
| 10 Years | rr_AverageAnnualReturnYear10 | 2.23% |
| Admiral | Vanguard Long-Term Treasury Index Fund | Return After Taxes on Distributions | Admiral Shares | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 2.25% |
| 5 Years | rr_AverageAnnualReturnYear05 | (2.33%) |
| 10 Years | rr_AverageAnnualReturnYear10 | 1.14% |
| Admiral | Vanguard Long-Term Treasury Index Fund | Return After Taxes on Distributions and Sale of Fund Shares | Admiral Shares | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 2.13% |
| 5 Years | rr_AverageAnnualReturnYear05 | (1.36%) |
| 10 Years | rr_AverageAnnualReturnYear10 | 1.29% |
| Admiral | Vanguard Long-Term Treasury Index Fund | Bloomberg U.S. Aggregate Float Adjusted Index (reflects no deduction for fees, expenses, or taxes) | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 5.60% |
| 5 Years | rr_AverageAnnualReturnYear05 | 1.17% |
| 10 Years | rr_AverageAnnualReturnYear10 | 1.83% |
| Admiral | Vanguard Long-Term Treasury Index Fund | Bloomberg U.S. Long Treasury Bond Index (reflects no deduction for fees, expenses, or taxes) | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 3.06% |
| 5 Years | rr_AverageAnnualReturnYear05 | (1.24%) |
| 10 Years | rr_AverageAnnualReturnYear10 | 2.28% |
| Admiral | Vanguard Long-Term Treasury Index Fund | Spliced Bloomberg U.S. Long Treasury Index in USD (reflects no deduction for fees, expenses, or taxes) | ||
| Risk Return Abstract | rr_RiskReturnAbstract | |
| 1 Year | rr_AverageAnnualReturnYear01 | 3.06% |
| 5 Years | rr_AverageAnnualReturnYear05 | (1.24%) |
| 10 Years | rr_AverageAnnualReturnYear10 | 2.27% |