Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	Vanguard Tax-Managed Funds
Prospectus Date	rr_ProspectusDate	Apr. 29, 2025
Admiral | Vanguard Developed Markets 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;">Fund Summary</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 benchmark index that measures the investment return of stocks issued by companies located in Canada and the major markets of Europe and the Pacific region.
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 3% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	3.00%
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 FTSE Developed All Cap ex US Index (the Index), a market-capitalization-weighted index that as of December 31, 2024, is made up of approximately 3,909 common stocks of large-, mid-, and small-cap companies located in Canada and the major markets of Europe and the Pacific region. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.
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	An investment in the Fund could lose money over short or long periods of time.You should expect the Fund’s share price and total return to fluctuate within a wide range. The Fund is subject to the following risks, which could affect the Fund’s performance:
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 Developed ex US Index reflects the performance of the FTSE Developed ex North America Index through December 20, 2015; the FTSE Developed All Cap ex US Transition Index through May 31, 2016; and the FTSE Developed All Cap ex US Index thereafter. Returns for the indexes shown are adjusted for withholding taxes applicable to U.S.-based mutual funds organized as Delaware statutory trusts. 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;">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 </span><span style="font-family:Arial;font-size:9.5pt;">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 Developed Markets Index Fund Admiral Shares</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, 2024</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 Developed Markets 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 Developed Markets 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 Developed Markets Index Fund | Stock Market Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	• Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund’s investments in foreign stocks can be riskier than U.S. stock investments. Foreign stocks may be more volatile and less liquid than U.S. stocks. The prices of foreign stocks and the prices of U.S. stocks may move in opposite directions. In addition, the Fund’s target index may, at times, become focused in stocks of a particular market sector, which would subject the Fund to proportionately higher exposure to the risks of that sector.
Admiral | Vanguard Developed Markets Index Fund | Country Regional Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	• Country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of securities issued by companies in foreign countries or regions. Because the Fund may invest a large portion of its assets in securities of companies located in any one country or region, the Fund’s performance may be hurt disproportionately by the poor performance of its investments in that area. Significant investments in Japan and the United Kingdom (U.K.) subject the Index and the Fund to proportionately higher exposure to Japanese and U.K. country risk.
Admiral | Vanguard Developed Markets Index Fund | Investment Style Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	• Investment style risk, which is the chance that returns from non-U.S. small- and mid-capitalization stocks will trail returns from global stock markets. Historically, non-U.S. small- and mid-cap stocks have been more volatile in price than the large-cap stocks that dominate the global markets, and they often perform quite differently. The stock prices of small and mid-size companies tend to experience greater volatility because, among other things, these companies tend to be more sensitive to changing economic conditions.
Admiral | Vanguard Developed Markets Index Fund | Currency Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	• Currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates.
Admiral | Vanguard Developed Markets Index Fund | index-related Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	• 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.
Admiral | Vanguard Developed Markets Index Fund | Index Replicating Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	• Index replicating risk, which is the chance that the Fund may be prevented from holding one or more securities in the same proportion as in its target index.
Admiral | Vanguard Developed Markets 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	0.04%
12b-1 Distribution Fee	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.05%	[1]
1 Year	rr_ExpenseExampleYear01	$ 5
3 Years	rr_ExpenseExampleYear03	16
5 Years	rr_ExpenseExampleYear05	28
10 Years	rr_ExpenseExampleYear10	$ 64
2015	rr_AnnualReturn2015	(0.18%)
2016	rr_AnnualReturn2016	2.45%
2017	rr_AnnualReturn2017	26.40%
2018	rr_AnnualReturn2018	(14.46%)
2019	rr_AnnualReturn2019	22.05%
2020	rr_AnnualReturn2020	10.26%
2021	rr_AnnualReturn2021	11.43%
Annual Return 2022	rr_AnnualReturn2022	(15.32%)
2023	rr_AnnualReturn2023	17.67%
2024	rr_AnnualReturn2024	3.04%
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	Jun. 30, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	17.52%
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, 2020
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(24.07%)
1 Year	rr_AverageAnnualReturnYear01	3.04%
5 Years	rr_AverageAnnualReturnYear05	4.76%
10 Years	rr_AverageAnnualReturnYear10	5.47%
Admiral | Vanguard Developed Markets Index Fund | Return After Taxes on Distributions | Admiral Shares
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	2.26%
5 Years	rr_AverageAnnualReturnYear05	4.03%
10 Years	rr_AverageAnnualReturnYear10	4.72%
Admiral | Vanguard Developed Markets Index Fund | Return After Taxes on Distributions and Sale of Fund Shares | Admiral Shares
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	2.38%
5 Years	rr_AverageAnnualReturnYear05	3.65%
10 Years	rr_AverageAnnualReturnYear10	4.25%
Admiral | Vanguard Developed Markets Index Fund | FTSE Developed All Cap ex US Index (reflects no deduction for fees or expenses)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	3.36%
5 Years	rr_AverageAnnualReturnYear05	4.79%
10 Years	rr_AverageAnnualReturnYear10	5.35%
Admiral | Vanguard Developed Markets Index Fund | Spliced Developed ex US Index (reflects no deduction for fees or expenses)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	3.36%
5 Years	rr_AverageAnnualReturnYear05	4.79%
10 Years	rr_AverageAnnualReturnYear10	5.43%
Admiral | Vanguard Developed Markets Index Fund | FTSE Global All Cap ex US Index (reflects no deduction for fees or expenses)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	5.53%
5 Years	rr_AverageAnnualReturnYear05	4.42%
10 Years	rr_AverageAnnualReturnYear10	5.13%

[1] The expense information shown in the table has been restated to reflect current fees.