v3.26.3
Inflation Protected Fund Investment Risks - Inflation Protected Fund
May 31, 2026
Inflation Indexed Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Inflation-Indexed Securities Risk. If the interest rate rises for reasons other than inflation, the value of inflation-indexed securities can be negatively impacted. In certain interest rate environments, such instruments may experience greater losses than other fixed income securities with similar durations.
Risks of Inflation Indexing Methodology [Member]  
Prospectus [Line Items]  
Risk [Text Block] Risks of Inflation Indexing Methodology. An inflation index may not accurately measure the real rate of inflation in the prices of goods and services, whether for the U.S. or a foreign country. Market perceptions of adjustment times or a lag between the time a security is adjusted for inflation and the time interest is paid can each adversely affect an inflation-indexed security, particularly during periods of significant, rapid changes in inflation.
Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk. Fixed income securities may be subject to volatility due to changes in interest rates. The value of fixed-income securities may decline when interest rates go up or increase when interest rates go down. The interest earned on fixed-income securities may decline when interest rates go down or increase when interest rates go up. Duration is a measure of interest rate risk that indicates how price-sensitive a bond is to changes in interest rates. Longer-term and lower coupon bonds tend to be more sensitive to changes in interest rates. For example, a bond with a duration of three years will decrease in value by approximately 3% if interest rates increase by 1%. Changing interest rates may have unpredictable effects on markets, may result in heightened market volatility, and could negatively impact the Fund’s performance. Any future changes in monetary policy made by central banks and/or their governments are likely to affect the level of interest rates.
Call or Prepayment Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Call or Prepayment Risk. During periods of falling interest rates, a bond issuer may “call” a bond to repay it before its maturity date. The Fund may only be able to invest the bond’s proceeds at lower interest rates, resulting in a decline in the Fund’s income.
Credit Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Credit Risk. The Fund may suffer losses if the issuer of a fixed income security owned by the Fund is unable to make interest or principal payments.
Foreign Investment Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Foreign Investment Risk. Investment in foreign securities involves risks due to several factors, such as illiquidity, the lack of public information, changes in the exchange rates between foreign currencies and the U.S. dollar, unfavorable political, social and legal developments, or economic and financial instability. Foreign companies are not subject to the U.S. accounting and financial reporting standards and may have riskier settlement procedures. U.S. investments that are denominated in foreign currencies or that are traded in foreign markets, or securities of U.S. companies that have significant foreign operations may be subject to foreign investment risk.
Emerging Markets Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Emerging Markets Risk. Investments in emerging markets are subject to all of the risks of investments in foreign securities, generally to a greater extent than in developed markets, and additional risks as well. Generally, the economic, social, legal, and political structures in emerging market countries are less diverse, mature and stable than those in developed countries. As a result, investments in emerging market securities tend to be more volatile than investments in developed countries. Unlike most developed countries, emerging market countries may impose restrictions on foreign investment. These countries may also impose confiscatory taxes on investment proceeds or otherwise restrict the ability of foreign investors to withdraw their money at will.
Currency Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Currency Risk. Because the Fund’s foreign investments are generally held in foreign currencies, the Fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar. Such gains or losses may be substantial.
Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk. The Fund’s share price can fall because of weakness in the broad market, a particular industry, or specific holdings or due to adverse social, political or economic developments here or abroad, changes in investor psychology, technological disruptions, or heavy institutional selling and other conditions or events (including, for example, military confrontations, war, terrorism, trade wars, disease/virus outbreaks and epidemics). The prices of individual securities may fluctuate, sometimes dramatically, from day to day. The prices of stocks and other equity securities tend to be more volatile than those of fixed-income securities.
US Government Obligations Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] U.S. Government Obligations Risk. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government and are generally considered to have low credit risk. Unlike U.S. Treasury obligations, securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government and are therefore subject to greater credit risk than securities issued or guaranteed by the U.S. Treasury.
Foreign Sovereign Debt Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Foreign Sovereign Debt Risk. Foreign sovereign debt securities are subject to the risk that a governmental entity may delay or refuse to pay interest or to repay principal on its sovereign debt, due, for example, to cash flow problems, insufficient foreign currency reserves, political, social and economic considerations, the relative size of the governmental entity’s debt position in relation to the economy or the failure to put in place economic reforms required by the International Monetary Fund or other multilateral agencies. If a governmental entity defaults, it may ask for more time in which to pay or for further loans.
Mortgage and Asset Backed Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Mortgage- and Asset-Backed Securities Risk. Mortgage-backed securities are similar to other debt securities in that they are subject to credit risk and interest rate risk. Mortgage-backed securities may be issued or guaranteed by the U.S. Government, its agencies or instrumentalities or may be non-guaranteed securities issued by private issuers. These securities are also subject to the risk that issuers will prepay the principal more quickly or more slowly than expected, which could cause the Fund to invest the proceeds in less attractive investments or increase the volatility of their prices. CMOs, which are a type of mortgage-backed security, may be less liquid and may exhibit greater price volatility than other types of mortgage- and asset-backed securities. Asset-backed securities are bonds or notes that are normally supported by a specific property. If the issuer fails to pay the interest or return the principal when the bond matures, then the issuer must give the property to the bondholders or noteholders. Examples of assets supporting asset-backed securities include credit card receivables, retail installment loans, home equity loans, auto loans, and manufactured housing loans.
Collateralized Loan Obligation Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Collateralized Loan Obligation Risk. A collateralized loan obligation is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. The cash flows from the trust are split into two or more portions, called tranches, varying in risk and yield. The riskiest portion is the “equity” tranche which bears the bulk of defaults from the bonds or loans in the trust and serves to protect the other, more senior tranches from default in all but the most severe circumstances. Because it is partially protected from defaults, a senior tranche from a collateralized loan obligation trust typically has higher ratings and lower yields than its underlying securities, and can be rated investment grade. Despite the protection from the equity tranche, collateralized loan obligation tranches can experience substantial losses due to actual defaults, increased sensitivity to defaults due to collateral default and disappearance of protecting tranches, market anticipation of defaults, as well as aversion to collateralized loan obligation securities as a class.
Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Derivatives Risk. The prices of derivatives may move in unexpected ways due to the use of leverage and other factors and may result in increased volatility or losses. The Fund may not be able to terminate or sell derivative positions, and a liquid secondary market may not always exist for derivative positions. When currency forwards are used by the Fund for hedging purposes, there is a risk that due to imperfect correlations, the currency forwards will not fully hedge against adverse changes in foreign currency values or, under extreme market conditions, will not provide any hedging benefit. The successful use of currency forwards for non-hedging purposes usually depends on the portfolio managers’ ability to forecast movements in foreign currency values and may be speculative. Should these values move in unexpected ways, the Fund may not achieve the anticipated benefit from using currency forwards, and it may realize losses, which could be significant.
Futures Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Futures Risk. A futures contract is considered a derivative because it derives its value from the price of the underlying currency, security or financial index. The prices of futures contracts can be volatile and futures contracts may lack liquidity. In addition, there may be imperfect or even negative correlation between the price of a futures contract and the price of the underlying currency, security or financial index.
Counterparty Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Counterparty Risk. Counterparty risk is the risk that a counterparty to a security, loan or derivative held by the Fund becomes bankrupt or otherwise fails to perform its obligations due to financial difficulties. The Fund may experience significant delays in obtaining any recovery in a bankruptcy or other reorganization proceeding, and there may be no recovery or limited recovery in such circumstances.
Hedging Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Hedging Risk. A hedge is an investment made in order to reduce the risk of adverse price movements in a currency or other investment by taking an offsetting position (often through a derivative instrument, such as an option or forward contract). While hedging strategies can be very useful and inexpensive ways of reducing risk, they are sometimes ineffective due to unexpected changes in the market. Hedging also involves the risk that changes in the value of the related security will not match those of the instruments being hedged as expected, in which case any losses on the instruments being hedged may not be reduced.
Active Trading Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Active Trading Risk. High portfolio turnover rates that are associated with active trading may result in higher transaction costs, which can adversely affect the Fund’s performance. Active trading tends to be more pronounced during periods of increased market volatility.
Securities Lending Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Securities Lending Risk. Engaging in securities lending could increase the market and credit risk for Fund investments. The Fund may lose money if it does not recover borrowed securities, the value of the collateral falls, or the value of investments made with cash collateral declines. The Fund’s loans will be collateralized by securities issued or guaranteed by the U.S. Government or its agencies and instrumentalities, which subjects the Fund to the credit risk of the U.S. Government or the issuing federal agency or instrumentality. If the value of either the cash collateral or the Fund’s investments of the cash collateral falls below the amount owed to a borrower, the Fund also may incur losses that exceed the amount it earned on lending the security. Securities lending also involves the risks of delay in receiving additional collateral or possible loss of rights in the collateral if the borrower fails. Another risk of securities lending is the risk that the loaned portfolio securities may not be available to the Fund on a timely basis and the Fund may therefore lose the opportunity to sell the securities at a desirable price.
Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] If the value of the assets of the Fund goes down, you could lose money.
Risk Not Insured Depository Institution [Member]  
Prospectus [Line Items]  
Risk [Text Block] Shares of the Fund are not bank deposits and are not guaranteed or insured by any bank, government entity or the Federal Deposit Insurance Corporation.