v3.25.1
Label Element Value
Risk Return Abstract rr_RiskReturnAbstract  
Registrant Name dei_EntityRegistrantName VANGUARD MALVERN FUNDS
Prospectus Date rr_ProspectusDate Mar. 26, 2025
ETF | Vanguard Short Duration Bond ETF  
Risk Return Abstract rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading <span style="font-family:Arial;font-size:13pt;font-weight:bold;">ETF Summary</span>
Objective [Heading] rr_ObjectiveHeading <span style="font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span>
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock The Fund seeks to provide high current income while maintaining limited price volatility.
Expense [Heading] rr_ExpenseHeading <span style="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 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="font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span>
Operating Expenses Caption [Text] rr_OperatingExpensesCaption <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="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="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. The Fund has no operating history and therefore has no portfolio turnover information.
Expense Example [Heading] rr_ExpenseExampleHeading <span style="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 shares with the cost of investing in other 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 sell your shares at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example Closing [Text Block] rr_ExpenseExampleClosingTextBlock This example does not include the brokerage commissions that you may pay to buy and sell shares of the Fund.
Strategy [Heading] rr_StrategyHeading <span style="font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span>
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock The Fund invests in fixed income securities of various maturities, yields, and qualities. Under normal circumstances, the Fund will invest at least 80% of its net assets (plus any borrowings for investment purposes) in bonds, which include fixed income securities such as corporate bonds; U.S. Treasury obligations and other U.S. government and agency securities; and asset-backed, mortgage-backed, and mortgage-related securities. In general, bonds purchased by the Fund will have a maturity of 90 days or more at the time of their issuance. The Fund may invest in fixed income securities of non-U.S. issuers, including emerging market countries.The Fund’s dollar-weighted average maturity will normally range between 1 and 5 years, and may either be longer or shorter under certain market conditions, such as during periods of market stress. The Fund’s average portfolio duration will normally range between 1 to 4 years. Since the Fund will have holdings in asset-backed, mortgage-backed, and similar securities, the Fund’s weighted average maturity may be approximate to the weighted average maturity of the cash flows in the securities held by the Fund, given certain prepayment assumptions. This is also known as weighted average life.The Fund can purchase bonds of any quality. High-quality fixed income securities are investment-grade securities that are rated the equivalent of A3 or better by Moody’s Investors Service, Inc. (Moody’s), or another independent rating agency or, if unrated, are determined to be of comparable quality by the Fund’s advisor. Medium-quality fixed income securities are investment-grade securities that are rated the equivalent of Baa1, Baa2, or Baa3 by Moody’s or another independent rating agency or, if unrated, are determined to be of comparable quality by the Fund’s advisor. Both high-quality and medium-quality fixed income securities are considered to be “investment-grade.” Lower quality fixed income securities—commonly known as “junk bonds”—are non-investment-grade securities that are rated the equivalent of Ba1 or lower by Moody’s Ratings or another independent rating agency or, if unrated, are determined to be of comparable quality by the Fund’s advisor. No more than 25% of the Fund’s assets may be invested in non-investment-grade fixed income securities, or junk bonds.The Fund may invest in derivatives instruments, such as options, futures contracts, or other swap agreements. The Fund may also invest in to be announced (“TBA”) mortgage-backed securities and take short positions in TBA securities. The Fund may also invest in structured product instruments, including asset-backed securities, agency and non-agency commercial and residential mortgage-backed securities, collateralized mortgage obligations, variable rate demand notes issued by government or government agencies, and collateralized loan obligations.The Fund seeks to have a majority of its assets denominated in or hedged back to the U.S. dollar but has the ability to invest in bonds denominated in a foreign currency on an unhedged basis. The Fund may attempt to hedge some or all of its foreign currency exposure, primarily through the use of foreign currency exchange contracts, in an effort to manage the currency risk associated with investing in securities denominated in currencies other than the U.S. dollar.
Risk [Heading] rr_RiskHeading <span style="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, and the level of risk may vary based on market conditions:• TBA Securities risk. A TBA transaction represents an agreement to buy or sell mortgage-backed securities with agreed-upon characteristics for a fixed unit price at a future date, but does not specify the particular security to be delivered. TBA transactions involve the risk that the value of the mortgage-backed securities to be purchased declines prior to settlement date or the counterparty does not deliver the securities as promised.Because the Fund is an exchange-traded fund (ETF) and the Fund’s shares are traded on an exchange, the Fund is subject to additional risks:
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading <span style="font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span>
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock This is the Fund’s initial prospectus, so it does not contain performance data.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess <span style="font-family:Arial;font-size:9.5pt;">This is the Fund’s initial prospectus, so it does not contain performance data.</span>
ETF | Vanguard Short Duration Bond ETF | 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.
ETF | Vanguard Short Duration Bond ETF | 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.
ETF | Vanguard Short Duration Bond ETF | Interest Rate Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Interest rate risk, which is the chance that bond prices overall will decline because of rising interest rates.
ETF | Vanguard Short Duration Bond ETF | Income Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Income risk, which is the chance that the Fund’s income will decline because of falling interest rates. A fund’s income declines when interest rates fall because the fund then must invest new cash flow and cash from maturing bonds in lower- yielding bonds. Income risk is generally high for short-term bond funds and moderate for intermediate-term bond funds, so investors should expect the Fund’s monthly income to fluctuate accordingly.
ETF | Vanguard Short Duration Bond ETF | Credit Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner or that negative perceptions of the issuer’s ability to make such payments will cause the price of that bond to decline.
ETF | Vanguard Short Duration Bond ETF | Manager Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Manager risk, which is the chance that poor security selection will cause the Fund to underperform relevant benchmarks or other funds with a similar investment objective.
ETF | Vanguard Short Duration Bond ETF | Call Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. The Fund would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund’s income. Such redemptions and subsequent reinvestments would also increase the Fund’s portfolio turnover rate. Call risk is generally low for short-term bonds, moderate for intermediate-term bonds, and higher for long-term bonds. The greater the call risk, the greater the chance for a decline in income and the potential for taxable capital gains.
ETF | Vanguard Short Duration Bond ETF | Prepayment Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Prepayment risk, which is the chance that during periods of falling interest rates, homeowners will refinance their mortgages before their maturity dates, resulting in prepayment of mortgage-backed securities held by the Fund. The Fund would then lose any price appreciation above the mortgage’s principal and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund’s income. Such prepayments and subsequent reinvestments would also increase the Fund’s portfolio turnover rate.
ETF | Vanguard Short Duration Bond ETF | Extension Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Extension risk, which is the chance that during periods of rising interest rates, certain debt securities will be paid off substantially more slowly than originally anticipated, and the value of those securities may fall. For funds that invest in mortgage-backed securities, extension risk is the chance that during periods of rising interest rates, homeowners will repay their mortgages at slower rates. This will lengthen the duration or average life of mortgage-backed securities held by the Fund and delay the Fund’s ability to reinvest proceeds at higher interest rates. Extension risk is generally high for high-yield bond funds.
ETF | Vanguard Short Duration Bond ETF | Derivatives Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Derivatives risk. The Fund may invest in derivatives, which may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.• Structured products risk. The Fund is subject to structured products risk. Structured products are subject to the risks associated with the underlying assets and may decline in value due to changes in the underlying assets. Certain structured products may be thinly traded or have a limited trading market, and as a result may be characterized as illiquid. Structured products are also subject to credit risk; the assets backing the structured product may be insufficient to pay interest or principal. In addition to the general risks associated with credit investments, structured products carry additional risks, including: the collateral may decline in value or default; the distributions from collateral securities may not be adequate to make interest or other payments; and the structured products may be subordinate to other classes.
ETF | Vanguard Short Duration Bond ETF | Emerging Markets Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Emerging markets risk, which is the chance that the bonds of governments, government agencies, government-owned corporations, and foreign companies located in emerging market countries will be substantially more volatile, and substantially less liquid, than the bonds of governments, government agencies, government-owned corporations, and foreign companies located in more developed foreign markets because, among other factors, emerging market countries can have more variable economic performance; greater custodial and operational risks; less developed legal, tax, regulatory, financial reporting, accounting, and record keeping systems; and greater political, social, and economic instability than developed markets.
ETF | Vanguard Short Duration Bond ETF | 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 and/or liquidity of securities issued by foreign governments, government agencies, government-owned corporations, and foreign companies. Because the Fund may invest in bonds of issuers 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. Country/regional risk is especially high in emerging market countries.
ETF | Vanguard Short Duration Bond ETF | 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. Currency risk is especially high in emerging markets.
ETF | Vanguard Short Duration Bond ETF | Currency Hedging Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Currency hedging risk. The Fund has the ability to invest in foreign bonds which may or may not be denominated in or hedged back to U.S. dollars. The Fund will decline in value if it underhedges a currency that has weakened or overhedges a currency that has strengthened relative to the U.S. dollar. In addition, the Fund will incur expenses to hedge its foreign currency exposure. By entering into currency hedging transactions, the Fund may eliminate any chance to benefit from favorable fluctuations in relevant currency exchange rates.
ETF | Vanguard Short Duration Bond ETF | Liquidity Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Liquidity risk, which is the chance that the Fund may not be able to sell a security in a timely manner at a desired price.
ETF | Vanguard Short Duration Bond ETF | Counterparty Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Counterparty risk, which is the chance that the counterparty to a derivatives contract, or other investment vehicle, with the Fund is unable or unwilling to meet its financial obligations.
ETF | Vanguard Short Duration Bond ETF | ETF exchange_volatility Risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • The Fund’s ETF Shares are listed for trading on Cboe BZX Exchange, Inc. and are bought and sold on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price and the NAV differ significantly. Thus, you may pay more or less than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.
ETF | Vanguard Short Duration Bond ETF | ETF_active trading_increased risk [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Although the Fund’s ETF Shares are listed for trading on Cboe BZX Exchange, Inc., it is possible that an active trading market may not be maintained.
ETF | Vanguard Short Duration Bond ETF | ETF_trading halted [Member]  
Risk Return Abstract rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock • Trading of the Fund’s ETF Shares may be halted by the activation of individual or marketwide trading halts (which halt trading for a specific period of time when the price of a particular security or overall market prices decline by a specified percentage). Trading of the Fund’s ETF Shares may also be halted if (1) the shares are delisted from Cboe BZX Exchange, Inc. without first being listed on another exchange or (2) Cboe BZX Exchange, Inc. officials determine that such action is appropriate in the interest of a fair and orderly market or for the protection of investors. Because of the speculative nature of junk bonds, you should carefully consider the risks associated with this Fund before you purchase shares.
ETF | Vanguard Short Duration Bond ETF | ETF Shares  
Risk Return Abstract rr_RiskReturnAbstract  
Management Fees rr_ManagementFeesOverAssets 0.08%
12b-1 Distribution Fee rr_DistributionAndService12b1FeesOverAssets none
Other Expenses rr_OtherExpensesOverAssets 0.07%
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 0.15% [1]
1 Year rr_ExpenseExampleYear01 $ 15
3 Years rr_ExpenseExampleYear03 48
Transaction Fee on Purchases and Sales malvern_TransactionFeeOnPurchasesandSales none [2]
Transaction Fee on Reinvested Dividends malvern_TransactionFeeOnReinvestedDividends none [2]
[1] The expense information shown in the table reflects estimated amounts for the current fiscal year.
[2] None through Vanguard (Broker fees vary)