v3.24.4
Investment Risks
Aug. 31, 2024
Schwab Short-Term Bond Index Fund | Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund is subject to risks, any of which could cause an investor to lose money.
Schwab Short-Term Bond Index Fund | Risk Money Market Fund May Impose Fees or Suspend Sales [Member]  
Prospectus [Line Items]  
Risk [Text Block] Certain underlying money market funds may impose a fee upon the sale of shares under certain circumstances.
Schwab Short-Term Bond Index Fund | Risk Money Market Fund May Not Preserve Dollar [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund may invest in underlying money market funds that seek to maintain a stable $1.00 net asset value.
Schwab Short-Term Bond Index Fund | Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk. Financial markets rise and fall in response to a variety of factors, sometimes rapidly and unpredictably. Markets may be impacted by economic, political, regulatory and other conditions, including economic sanctions and other government actions. In addition, the occurrence of global events, such as war, terrorism, environmental disasters, natural disasters and epidemics, may also negatively affect the financial markets. As with any investment whose performance is tied to these markets, the value of an investment in the fund will fluctuate, which means that an investor could lose money over short or long periods.
Schwab Short-Term Bond Index Fund | Investment Style Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Investment Style Risk. The fund is an index fund. Therefore, the fund follows the securities included in the index during upturns as well as downturns. Because of its indexing strategy, the fund does not take steps to reduce market exposure or to lessen the effects of a declining market. In addition, because of the fund’s expenses, the fund’s performance may be below that of the index. Errors relating to the index may occur from time to time and may not be identified by the index provider for a period of time. In addition, market disruptions could cause delays in the index’s rebalancing schedule. Such errors and/or market disruptions may result in losses for the fund.
Schwab Short-Term Bond Index Fund | Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk. Interest rates rise and fall over time. As with any investment whose yield reflects current interest rates, the fund’s yield will change over time. During periods when interest rates are low, the fund’s yield (and total return) also may be low. Changes or the anticipation of changes in interest rates also may affect the fund’s share price: a rise in interest rates generally causes the fund’s share price to fall. The longer the fund’s portfolio duration, the more sensitive to interest rate movements its share price is likely to be. Also, a change in a central bank’s monetary policy or economic conditions, among other things, may result in a change in interest rates, which could have sudden and unpredictable effects on the markets and significantly impact the value of fixed-income securities in which the fund invests. A sudden or unpredictable rise in interest rates may cause volatility and the value of fixed-income securities to decline.
Schwab Short-Term Bond Index Fund | Credit Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Credit Risk. A decline in the credit quality of an issuer, guarantor or liquidity provider of a portfolio investment or a counterparty could cause the fund to lose money or underperform. The fund could lose money if, due to a decline in credit quality, the issuer, guarantor or liquidity provider of a portfolio investment or a counterparty fails to make, or is perceived as being unable or unwilling to make, timely principal or interest payments or otherwise honor its obligations.
Schwab Short-Term Bond Index Fund | Sampling Index Tracking Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Sampling Index Tracking Risk. The fund may not fully replicate the index and may hold securities not included in the index. As a result, the fund is subject to the risk that the investment adviser’s investment management strategy, the implementation of which is subject to a number of constraints, may not produce the intended results. Because the fund utilizes a sampling approach it may not track the return of the index as well as it would if the fund purchased all of the securities in the index.
Schwab Short-Term Bond Index Fund | Tracking Error and Correlation Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Tracking Error and Correlation Risk. As an index fund, the fund seeks to track the performance of the index, although it may not be successful in doing so. Further, there can be no guarantee that the fund will achieve a high degree of correlation between the fund’s performance and that of its index. The correlation between the performance of the fund and that of its index, positive or negative, is called “tracking error.” Tracking error can be caused by many factors and it may be significant.
Schwab Short-Term Bond Index Fund | Prepayment and Extension Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Prepayment and Extension Risk. Certain fixed-income securities are subject to the risk that the securities may be paid off earlier or later than expected, especially during periods of falling or rising interest rates, respectively. Prepayments of obligations could cause the fund to forgo future interest income on the portion of the security’s principal repaid early and force the fund to reinvest that money at the lower prevailing interest rates. Extensions of obligations could cause the fund to exhibit additional volatility and hold securities paying lower-than-market rates of interest. Either case could hurt the fund’s performance.
Schwab Short-Term Bond Index Fund | Non-U.S. Issuer Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Non-U.S. Issuer Risk. The fund may invest in U.S.-registered, dollar-denominated bonds of non-U.S. corporations, governments, agencies and supra-national entities. The fund’s investments in bonds of non-U.S. issuers may involve certain risks that are greater than those associated with investments in securities of U.S. issuers. These include risks of adverse changes in foreign economic, political, regulatory and other conditions; the imposition of economic sanctions or other government restrictions; differing accounting, auditing, financial reporting and legal standards and practices; differing securities market structures; and higher transaction costs. These risks may be heightened in connection with bonds issued by non-U.S. corporations and entities in emerging markets.
Schwab Short-Term Bond Index Fund | Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Derivatives Risk. The fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. The fund’s use of derivatives could reduce the fund’s performance, increase its volatility and cause the fund to lose more than the initial amount invested. In addition, investments in derivatives may involve leverage, which means a small percentage of assets invested in derivatives can have a disproportionately large impact on the fund.
Schwab Short-Term Bond Index Fund | Liquidity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Liquidity Risk. The fund may be unable to sell certain securities, such as illiquid securities, readily at a favorable time or price, or the fund may have to sell them at a loss.
Schwab Short-Term Bond Index Fund | Concentration Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Concentration Risk. To the extent that the fund’s or the index’s portfolio is concentrated in the securities of issuers in a particular market, industry, group of industries, sector or asset class, the fund may be adversely affected by the performance of those securities, may be subject to increased price volatility and may be more vulnerable to adverse economic, market, political or regulatory occurrences affecting that market, industry, group of industries, sector or asset class.
Schwab Short-Term Bond Index Fund | Leverage Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Leverage Risk. Certain fund transactions, such as derivatives transactions and mortgage dollar rolls, may give rise to a form of leverage and may expose the fund to greater risk. Leverage tends to magnify the effect of any decrease or increase in the value of the fund’s portfolio securities. The use of leverage may cause the fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations.
Schwab Short-Term Bond Index Fund | Securities Lending Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Securities Lending Risk. Securities lending involves the risk of loss of rights in, or delay in recovery of, the loaned securities if the borrower fails to return the security loaned or becomes insolvent.
Schwab Short-Term Bond Index Fund | Money Market Fund Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Money Market Fund Risk. The fund may invest in underlying money market funds that seek to maintain a stable $1.00 net asset value. Although an underlying money market fund seeks to maintain a stable $1.00 net asset value, it is possible to lose money by investing in such a money market fund. In addition, money market funds are not designed to offer capital appreciation. Certain underlying money market funds may impose a fee upon the sale of shares under certain circumstances.
Schwab Treasury Inflation Protected Securities Index Fund | Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund is subject to risks, any of which could cause an investor to lose money.
Schwab Treasury Inflation Protected Securities Index Fund | Risk Money Market Fund May Impose Fees or Suspend Sales [Member]  
Prospectus [Line Items]  
Risk [Text Block] Certain underlying money market funds may impose a fee upon the sale of shares under certain circumstances.
Schwab Treasury Inflation Protected Securities Index Fund | Risk Money Market Fund May Not Preserve Dollar [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund may invest in underlying money market funds that seek to maintain a stable $1.00 net asset value.
Schwab Treasury Inflation Protected Securities Index Fund | Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk. Financial markets rise and fall in response to a variety of factors, sometimes rapidly and unpredictably. Markets may be impacted by economic, political, regulatory and other conditions, including economic sanctions and other government actions. In addition, the occurrence of global events, such as war, terrorism, environmental disasters, natural disasters and epidemics, may also negatively affect the financial markets. As with any investment whose performance is tied to these markets, the value of an investment in the fund will fluctuate, which means that an investor could lose money over short or long periods.
Schwab Treasury Inflation Protected Securities Index Fund | Investment Style Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Investment Style Risk. The fund is an index fund. Therefore, the fund follows the securities included in the index during upturns as well as downturns. Because of its indexing strategy, the fund does not take steps to reduce market exposure or to lessen the effects of a declining market. In addition, because of the fund’s expenses, the fund’s performance may be below that of the index. Errors relating to the index may occur from time to time and may not be identified by the index provider for a period of time. In addition, market disruptions could cause delays in the index’s rebalancing schedule. Such errors and/or market disruptions may result in losses for the fund.
Schwab Treasury Inflation Protected Securities Index Fund | Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk. Interest rates rise and fall over time. As with any investment whose yield reflects current interest rates, the fund’s yield will change over time. During periods when interest rates are low, the fund’s yield (and total return) also may be low. Changes or the anticipation of changes in interest rates also may affect the fund’s share price: a rise in interest rates generally causes the fund’s share price to fall. The longer the fund’s portfolio duration, the more sensitive to interest rate movements its share price is likely to be. Also, a change in a central bank’s monetary policy or economic conditions, among other things, may result in a change in interest rates, which could have sudden and unpredictable effects on the markets and significantly impact the value of fixed-income securities in which the fund invests. A sudden or unpredictable rise in interest rates may cause volatility and the value of fixed-income securities to decline.
Schwab Treasury Inflation Protected Securities Index Fund | Credit Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Credit Risk. A decline in the credit quality of an issuer, guarantor or liquidity provider of a portfolio investment or a counterparty could cause the fund to lose money or underperform. The fund could lose money if, due to a decline in credit quality, the issuer, guarantor or liquidity provider of a portfolio investment or a counterparty fails to make, or is perceived as being unable or unwilling to make, timely principal or interest payments or otherwise honor its obligations.
Schwab Treasury Inflation Protected Securities Index Fund | Sampling Index Tracking Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Sampling Index Tracking Risk. To the extent the fund uses sampling techniques, the fund will not fully replicate the index and may hold securities not included in the index. As a result, the fund will be subject to the risk that the investment adviser’s investment management strategy, the implementation of which is subject to a number of constraints, may not produce the intended results. If the fund utilizes a sampling approach, it may not track the return of the index as well as it would if the fund purchased all of the securities in the index.
Schwab Treasury Inflation Protected Securities Index Fund | Tracking Error and Correlation Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Tracking Error and Correlation Risk. As an index fund, the fund seeks to track the performance of the index, although it may not be successful in doing so. Further, there can be no guarantee that the fund will achieve a high degree of correlation between the fund’s performance and that of its index. The correlation between the performance of the fund and that of its index, positive or negative, is called “tracking error.” Tracking error can be caused by many factors and it may be significant.
Schwab Treasury Inflation Protected Securities Index Fund | Liquidity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Liquidity Risk. The fund may be unable to sell certain securities, such as illiquid securities, readily at a favorable time or price, or the fund may have to sell them at a loss.
Schwab Treasury Inflation Protected Securities Index Fund | Securities Lending Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Securities Lending Risk. Securities lending involves the risk of loss of rights in, or delay in recovery of, the loaned securities if the borrower fails to return the security loaned or becomes insolvent.
Schwab Treasury Inflation Protected Securities Index Fund | Money Market Fund Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Money Market Fund Risk. The fund may invest in underlying money market funds that seek to maintain a stable $1.00 net asset value. Although an underlying money market fund seeks to maintain a stable $1.00 net asset value, it is possible to lose money by investing in such a money market fund. In addition, money market funds are not designed to offer capital appreciation. Certain underlying money market funds may impose a fee upon the sale of shares under certain circumstances.
Schwab Treasury Inflation Protected Securities Index Fund | Inflation-Protected Security Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Inflation-Protected Security Risk. The value of inflation-protected securities, including TIPS, generally will fluctuate in response to changes in “real” interest rates, generally decreasing when real interest rates rise and increasing when real interest rates fall. Real interest rates represent nominal (or stated) interest rates reduced by the expected impact of inflation. In addition, interest payments on inflation-indexed securities will generally vary up or down along with the rate of inflation.
Schwab U.S. Aggregate Bond Index Fund | Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund is subject to risks, any of which could cause an investor to lose money.
Schwab U.S. Aggregate Bond Index Fund | Risk Money Market Fund May Impose Fees or Suspend Sales [Member]  
Prospectus [Line Items]  
Risk [Text Block] Certain underlying money market funds may impose a fee upon the sale of shares under certain circumstances.
Schwab U.S. Aggregate Bond Index Fund | Risk Money Market Fund May Not Preserve Dollar [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund may invest in underlying money market funds that seek to maintain a stable $1.00 net asset value.
Schwab U.S. Aggregate Bond Index Fund | Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk. Financial markets rise and fall in response to a variety of factors, sometimes rapidly and unpredictably. Markets may be impacted by economic, political, regulatory and other conditions, including economic sanctions and other government actions. In addition, the occurrence of global events, such as war, terrorism, environmental disasters, natural disasters and epidemics, may also negatively affect the financial markets. As with any investment whose performance is tied to these markets, the value of an investment in the fund will fluctuate, which means that an investor could lose money over short or long periods.
Schwab U.S. Aggregate Bond Index Fund | Investment Style Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Investment Style Risk. The fund is an index fund. Therefore, the fund follows the securities included in the index during upturns as well as downturns. Because of its indexing strategy, the fund does not take steps to reduce market exposure or to lessen the effects of a declining market. In addition, because of the fund’s expenses, the fund’s performance may be below that of the index. Errors relating to the index may occur from time to time and may not be identified by the index provider for a period of time. In addition, market disruptions could cause delays in the index’s rebalancing schedule. Such errors and/or market disruptions may result in losses for the fund.
Schwab U.S. Aggregate Bond Index Fund | Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk. Interest rates rise and fall over time. As with any investment whose yield reflects current interest rates, the fund’s yield will change over time. During periods when interest rates are low, the fund’s yield (and total return) also may be low. Changes or the anticipation of changes in interest rates also may affect the fund’s share price: a rise in interest rates generally causes the fund’s share price to fall. The longer the fund’s portfolio duration, the more sensitive to interest rate movements its share price is likely to be. Also, a change in a central bank’s monetary policy or economic conditions, among other things, may result in a change in interest rates, which could have sudden and unpredictable effects on the markets and significantly impact the value of fixed-income securities in which the fund invests. A sudden or unpredictable rise in interest rates may cause volatility and the value of fixed-income securities to decline.
Schwab U.S. Aggregate Bond Index Fund | Credit Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Credit Risk. A decline in the credit quality of an issuer, guarantor or liquidity provider of a portfolio investment or a counterparty could cause the fund to lose money or underperform. The fund could lose money if, due to a decline in credit quality, the issuer, guarantor or liquidity provider of a portfolio investment or a counterparty fails to make, or is perceived as being unable or unwilling to make, timely principal or interest payments or otherwise honor its obligations.
Schwab U.S. Aggregate Bond Index Fund | Sampling Index Tracking Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Sampling Index Tracking Risk. The fund may not fully replicate the index and may hold securities not included in the index. As a result, the fund is subject to the risk that the investment adviser’s investment management strategy, the implementation of which is subject to a number of constraints, may not produce the intended results. Because the fund utilizes a sampling approach it may not track the return of the index as well as it would if the fund purchased all of the securities in the index.
Schwab U.S. Aggregate Bond Index Fund | Tracking Error and Correlation Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Tracking Error and Correlation Risk. As an index fund, the fund seeks to track the performance of the index, although it may not be successful in doing so. Further, there can be no guarantee that the fund will achieve a high degree of correlation between the fund’s performance and that of its index. The correlation between the performance of the fund and that of its index, positive or negative, is called “tracking error.” Tracking error can be caused by many factors and it may be significant.
Schwab U.S. Aggregate Bond Index Fund | Prepayment and Extension Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Prepayment and Extension Risk. Certain fixed-income securities are subject to the risk that the securities may be paid off earlier or later than expected, especially during periods of falling or rising interest rates, respectively. Prepayments of obligations could cause the fund to forgo future interest income on the portion of the security’s principal repaid early and force the fund to reinvest that money at the lower prevailing interest rates. Extensions of obligations could cause the fund to exhibit additional volatility and hold securities paying lower-than-market rates of interest. Either case could hurt the fund’s performance.
Schwab U.S. Aggregate Bond Index Fund | Non-U.S. Issuer Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Non-U.S. Issuer Risk. The fund may invest in U.S.-registered, dollar-denominated bonds of non-U.S. corporations, governments, agencies and supra-national entities. The fund’s investments in bonds of non-U.S. issuers may involve certain risks that are greater than those associated with investments in securities of U.S. issuers. These include risks of adverse changes in foreign economic, political, regulatory and other conditions; the imposition of economic sanctions or other government restrictions; differing accounting, auditing, financial reporting and legal standards and practices; differing securities market structures; and higher transaction costs. These risks may be heightened in connection with bonds issued by non-U.S. corporations and entities in emerging markets.
Schwab U.S. Aggregate Bond Index Fund | Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Derivatives Risk. The fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. The fund’s use of derivatives could reduce the fund’s performance, increase its volatility and cause the fund to lose more than the initial amount invested. In addition, investments in derivatives may involve leverage, which means a small percentage of assets invested in derivatives can have a disproportionately large impact on the fund.
Schwab U.S. Aggregate Bond Index Fund | Liquidity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Liquidity Risk. The fund may be unable to sell certain securities, such as illiquid securities, readily at a favorable time or price, or the fund may have to sell them at a loss.
Schwab U.S. Aggregate Bond Index Fund | Concentration Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Concentration Risk. To the extent that the fund’s or the index’s portfolio is concentrated in the securities of issuers in a particular market, industry, group of industries, sector or asset class, the fund may be adversely affected by the performance of those securities, may be subject to increased price volatility and may be more vulnerable to adverse economic, market, political or regulatory occurrences affecting that market, industry, group of industries, sector or asset class.
Schwab U.S. Aggregate Bond Index Fund | Leverage Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Leverage Risk. Certain fund transactions, such as TBA transactions or derivatives transactions, may give rise to a form of leverage and may expose the fund to greater risk. Leverage tends to magnify the effect of any decrease or increase in the value of the fund’s portfolio securities. The use of leverage may cause the fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations.
Schwab U.S. Aggregate Bond Index Fund | Securities Lending Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Securities Lending Risk. Securities lending involves the risk of loss of rights in, or delay in recovery of, the loaned securities if the borrower fails to return the security loaned or becomes insolvent.
Schwab U.S. Aggregate Bond Index Fund | Money Market Fund Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Money Market Fund Risk. The fund may invest in underlying money market funds that seek to maintain a stable $1.00 net asset value. Although an underlying money market fund seeks to maintain a stable $1.00 net asset value, it is possible to lose money by investing in such a money market fund. In addition, money market funds are not designed to offer capital appreciation. Certain underlying money market funds may impose a fee upon the sale of shares under certain circumstances.
Schwab U.S. Aggregate Bond Index Fund | Portfolio Turnover Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Portfolio Turnover Risk. The fund may engage in frequent trading of its portfolio securities in connection with its tracking of the index or in response to market conditions. A higher portfolio turnover rate may result in increased transaction costs, which may lower the fund’s performance. A higher portfolio turnover rate can also result in an increase in taxable capital gains distributions to the fund’s shareholders.
Schwab U.S. Aggregate Bond Index Fund | Mortgage-Backed and Mortgage Pass-Through Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Mortgage-Backed and Mortgage Pass-Through Securities Risk. Mortgage-backed securities tend to increase in value less than other debt securities when interest rates decline, but are subject to similar or greater risk of decline in market value during periods of rising interest rates. Certain of the mortgage-backed securities in which the fund may invest are issued or guaranteed by agencies or instrumentalities of the U.S. government but are not backed by the full faith and credit of the U.S. government. There can be no assurance that the U.S. government would provide financial support to its agencies or instrumentalities where it was not obligated to do so which can cause the fund to lose money or underperform. The risks of investing in mortgage-backed securities include, among others, interest rate risk, credit risk, prepayment risk and extension risk. Transactions in mortgage pass-through securities often occur through TBA transactions. The fund could lose money or underperform if a TBA counterparty defaults or goes bankrupt.
Schwab U.S. Aggregate Bond Index Fund | Mortgage Dollar Rolls Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Mortgage Dollar Rolls Risk. Mortgage dollar rolls are transactions in which the fund sells mortgage-backed securities to a dealer and simultaneously agrees to repurchase similar securities in the future at a predetermined price. The fund’s mortgage dollar rolls could lose money if the price of the mortgage-backed securities sold falls below the agreed upon repurchase price, or if the counterparty is unable to honor the agreement.
Schwab Tax-Free Bond Fund | Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund is subject to risks, any of which could cause an investor to lose money.
Schwab Tax-Free Bond Fund | Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk. Financial markets rise and fall in response to a variety of factors, sometimes rapidly and unpredictably. Markets may be impacted by economic, political, regulatory and other conditions, including economic sanctions and other government actions. In addition, the occurrence of global events, such as war, terrorism, environmental disasters, natural disasters and epidemics, may also negatively affect the financial markets. As with any investment whose performance is tied to these markets, the value of an investment in the fund will fluctuate, which means that an investor could lose money over short or long periods.
Schwab Tax-Free Bond Fund | Investment Style Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Investment Style Risk. The fund is not designed to offer substantial capital appreciation. In exchange for its goal of capital preservation, the fund may offer lower long-term performance than stock investments or certain other types of bond investments. The fund’s emphasis on quality and preservation of capital also could cause it to underperform certain other types of bond investments, particularly those that take greater maturity and credit risks. At the same time, some of the fund’s investments may have greater risks than investments in some taxable bonds.
Schwab Tax-Free Bond Fund | Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk. Interest rates rise and fall over time. As with any investment whose yield reflects current interest rates, the fund’s yield will change over time. During periods when interest rates are low, the fund’s yield (and total return) also may be low. Changes or the anticipation of changes in interest rates also may affect the fund’s share price: a rise in interest rates generally causes the fund’s share price to fall. The longer the fund’s portfolio duration, the more sensitive to interest rate movements its share price is likely to be. Also, a change in a central bank’s monetary policy or economic conditions, among other things, may result in a change in interest rates, which could have sudden and unpredictable effects on the markets and significantly impact the value of fixed-income securities in which the fund invests. A sudden or unpredictable rise in interest rates may cause volatility and the value of fixed-income securities to decline.
Schwab Tax-Free Bond Fund | Credit Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Credit Risk. A decline in the credit quality of an issuer, guarantor or liquidity provider of a portfolio investment or a counterparty could cause the fund to lose money or underperform. The fund could lose money if, due to a decline in credit quality, the issuer, guarantor or liquidity provider of a portfolio investment or a counterparty fails to make, or is perceived as being unable or unwilling to make, timely principal or interest payments or otherwise honor its obligations.
Schwab Tax-Free Bond Fund | Prepayment and Extension Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Prepayment and Extension Risk. Certain fixed-income securities are subject to the risk that the securities may be paid off earlier or later than expected, especially during periods of falling or rising interest rates, respectively. Prepayments of obligations could cause the fund to forgo future interest income on the portion of the security’s principal repaid early and force the fund to reinvest that money at the lower prevailing interest rates. Extensions of obligations could cause the fund to exhibit additional volatility and hold securities paying lower-than-market rates of interest. Either case could hurt the fund’s performance.
Schwab Tax-Free Bond Fund | Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Derivatives Risk. The fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. The fund’s use of derivatives could reduce the fund’s performance, increase its volatility and cause the fund to lose more than the initial amount invested. In addition, investments in derivatives may involve leverage, which means a small percentage of assets invested in derivatives can have a disproportionately large impact on the fund.
Schwab Tax-Free Bond Fund | Liquidity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Liquidity Risk. The fund may be unable to sell certain securities, such as illiquid securities, readily at a favorable time or price, or the fund may have to sell them at a loss.
Schwab Tax-Free Bond Fund | Portfolio Turnover Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Portfolio Turnover Risk. High portfolio turnover may result in the fund paying higher levels of transaction costs and may generate greater tax liabilities for shareholders. Portfolio turnover risk may cause the fund’s performance to be less than expected.
Schwab Tax-Free Bond Fund | Management Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Management Risk. As an actively managed mutual fund, the fund is subject to the risk that its investment adviser will select investments or allocate assets in a manner that could cause the fund to underperform or otherwise not meet its investment objective. The fund’s investment adviser applies its own investment techniques and risk analyses in making investment decisions for the fund, but there can be no guarantee that they will produce the desired results.
Schwab Tax-Free Bond Fund | Municipal Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Municipal Securities Risk. The fund primarily invests in municipal securities whose interest, in the opinion of the issuers’ counsel, is exempt from federal income tax and from the AMT. Neither the investment adviser nor the fund guarantees that this opinion is correct, and there is no assurance that the Internal Revenue Service (IRS) will agree with such counsel’s opinion. If certain types of investments the fund buys as tax-exempt are later ruled to be taxable, a portion of the fund’s income could be taxable. To the extent that the fund invests in municipal securities from a given state or geographic region, its share price and performance could be affected by local, state and regional factors, including erosion of the tax base and changes in the economic climate. In addition, many municipal securities are issued to finance specific projects (especially those relating to education, health care, transportation and utilities) and conditions in those sectors can affect the overall municipal market. National governmental actions, such as the elimination of tax-exempt status or the reduction of financial support to municipalities, also could affect performance. Some municipalities are experiencing difficulties in the current economic and political environment.
Schwab Tax-Free Bond Fund | High-Yield Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] High-Yield Risk. High-yield securities and unrated securities of similar credit quality (junk bonds) are subject to greater levels of credit and liquidity risks, and may be more volatile than higher-rated securities. High-yield securities are considered predominately speculative with respect to the issuer’s continuing ability to make principal and interest payments.
Schwab Tax-Free Bond Fund | Taxable Investments Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Taxable Investments Risk. The fund may invest a portion of its assets in securities that generate income that is not exempt from federal income tax and in securities whose interest is subject to the AMT. These investments could generate taxable income for shareholders.
Schwab California Tax-Free Bond Fund | Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund is subject to risks, any of which could cause an investor to lose money.
Schwab California Tax-Free Bond Fund | Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk. Financial markets rise and fall in response to a variety of factors, sometimes rapidly and unpredictably. Markets may be impacted by economic, political, regulatory and other conditions, including economic sanctions and other government actions. In addition, the occurrence of global events, such as war, terrorism, environmental disasters, natural disasters and epidemics, may also negatively affect the financial markets. As with any investment whose performance is tied to these markets, the value of an investment in the fund will fluctuate, which means that an investor could lose money over short or long periods.
Schwab California Tax-Free Bond Fund | Investment Style Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Investment Style Risk. The fund is not designed to offer substantial capital appreciation. In exchange for its goal of capital preservation, the fund may offer lower long-term performance than stock investments or certain other types of bond investments. The fund’s emphasis on quality and preservation of capital also could cause it to underperform certain other types of bond investments, particularly those that take greater maturity and credit risks. At the same time, some of the fund’s investments may have greater risks than investments in some taxable bonds.
Schwab California Tax-Free Bond Fund | Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk. Interest rates rise and fall over time. As with any investment whose yield reflects current interest rates, the fund’s yield will change over time. During periods when interest rates are low, the fund’s yield (and total return) also may be low. Changes or the anticipation of changes in interest rates also may affect the fund’s share price: a rise in interest rates generally causes the fund’s share price to fall. The longer the fund’s portfolio duration, the more sensitive to interest rate movements its share price is likely to be. Also, a change in a central bank’s monetary policy or economic conditions, among other things, may result in a change in interest rates, which could have sudden and unpredictable effects on the markets and significantly impact the value of fixed-income securities in which the fund invests. A sudden or unpredictable rise in interest rates may cause volatility and the value of fixed-income securities to decline.
Schwab California Tax-Free Bond Fund | Credit Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Credit Risk. A decline in the credit quality of an issuer, guarantor or liquidity provider of a portfolio investment or a counterparty could cause the fund to lose money or underperform. The fund could lose money if, due to a decline in credit quality, the issuer, guarantor or liquidity provider of a portfolio investment or a counterparty fails to make, or is perceived as being unable or unwilling to make, timely principal or interest payments or otherwise honor its obligations.
Schwab California Tax-Free Bond Fund | Prepayment and Extension Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Prepayment and Extension Risk. Certain fixed-income securities are subject to the risk that the securities may be paid off earlier or later than expected, especially during periods of falling or rising interest rates, respectively. Prepayments of obligations could cause the fund to forgo future interest income on the portion of the security’s principal repaid early and force the fund to reinvest that money at the lower prevailing interest rates. Extensions of obligations could cause the fund to exhibit additional volatility and hold securities paying lower-than-market rates of interest. Either case could hurt the fund’s performance.
Schwab California Tax-Free Bond Fund | Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Derivatives Risk. The fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. The fund’s use of derivatives could reduce the fund’s performance, increase its volatility and cause the fund to lose more than the initial amount invested. In addition, investments in derivatives may involve leverage, which means a small percentage of assets invested in derivatives can have a disproportionately large impact on the fund.
Schwab California Tax-Free Bond Fund | Liquidity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Liquidity Risk. The fund may be unable to sell certain securities, such as illiquid securities, readily at a favorable time or price, or the fund may have to sell them at a loss.
Schwab California Tax-Free Bond Fund | Management Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Management Risk. As an actively managed mutual fund, the fund is subject to the risk that its investment adviser will select investments or allocate assets in a manner that could cause the fund to underperform or otherwise not meet its investment objective. The fund’s investment adviser applies its own investment techniques and risk analyses in making investment decisions for the fund, but there can be no guarantee that they will produce the desired results.
Schwab California Tax-Free Bond Fund | Municipal Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Municipal Securities Risk. The fund primarily invests in municipal securities whose interest, in the opinion of the issuers’ counsel, is exempt from federal income tax and from the AMT. Neither the investment adviser nor the fund guarantees that this opinion is correct, and there is no assurance that the Internal Revenue Service (IRS) will agree with such counsel’s opinion. If certain types of investments the fund buys as tax-exempt are later ruled to be taxable, a portion of the fund’s income could be taxable. To the extent that the fund invests in municipal securities from a given state or geographic region, its share price and performance could be affected by local, state and regional factors, including erosion of the tax base and changes in the economic climate. In addition, many municipal securities are issued to finance specific projects (especially those relating to education, health care, transportation and utilities) and conditions in those sectors can affect the overall municipal market. National governmental actions, such as the elimination of tax-exempt status or the reduction of financial support to municipalities, also could affect performance. Some municipalities are experiencing difficulties in the current economic and political environment.
Schwab California Tax-Free Bond Fund | High-Yield Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] High-Yield Risk. High-yield securities and unrated securities of similar credit quality (junk bonds) are subject to greater levels of credit and liquidity risks, and may be more volatile than higher-rated securities. High-yield securities are considered predominately speculative with respect to the issuer’s continuing ability to make principal and interest payments.
Schwab California Tax-Free Bond Fund | Taxable Investments Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Taxable Investments Risk. The fund may invest a portion of its assets in securities that generate income that is not exempt from federal and California state income tax and in securities whose interest is subject to the AMT. These investments could generate taxable income for shareholders.
Schwab California Tax-Free Bond Fund | California State-Specific Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] California State-Specific Risk. Because the fund concentrates its investments in California municipal securities, the fund may be affected significantly by economic, regulatory, social or political developments affecting the ability of California issuers to pay interest or repay principal.
Schwab Opportunistic Municipal Bond Fund | Risk Lose Money [Member]  
Prospectus [Line Items]  
Risk [Text Block] The fund is subject to risks, any of which could cause an investor to lose money.
Schwab Opportunistic Municipal Bond Fund | Market Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Market Risk. Financial markets rise and fall in response to a variety of factors, sometimes rapidly and unpredictably. Markets may be impacted by economic, political, regulatory and other conditions, including economic sanctions and other government actions. In addition, the occurrence of global events, such as war, terrorism, environmental disasters, natural disasters and epidemics, may also negatively affect the financial markets. As with any investment whose performance is tied to these markets, the value of an investment in the fund will fluctuate, which means that an investor could lose money over short or long periods.
Schwab Opportunistic Municipal Bond Fund | Investment Style Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Investment Style Risk. The fund is not designed to offer substantial capital appreciation. In exchange for its goal of capital preservation, the fund may offer lower long-term performance than stock investments or certain other types of bond investments. Some of the fund’s investments may have greater risks than investments in some taxable bonds.
Schwab Opportunistic Municipal Bond Fund | Interest Rate Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Interest Rate Risk. Interest rates rise and fall over time. As with any investment whose yield reflects current interest rates, the fund’s yield will change over time. During periods when interest rates are low, the fund’s yield (and total return) also may be low. Changes or the anticipation of changes in interest rates also may affect the fund’s share price: a rise in interest rates generally causes the fund’s share price to fall. The longer the fund’s portfolio duration, the more sensitive to interest rate movements its share price is likely to be. Also, a change in a central bank’s monetary policy or economic conditions, among other things, may result in a change in interest rates, which could have sudden and unpredictable effects on the markets and significantly impact the value of fixed-income securities in which the fund invests. A sudden or unpredictable rise in interest rates may cause volatility and the value of fixed-income securities to decline.
Schwab Opportunistic Municipal Bond Fund | Credit Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Credit Risk. A decline in the credit quality of an issuer, guarantor or liquidity provider of a portfolio investment or a counterparty could cause the fund to lose money or underperform. The fund could lose money if, due to a decline in credit quality, the issuer, guarantor or liquidity provider of a portfolio investment or a counterparty fails to make, or is perceived as being unable or unwilling to make, timely principal or interest payments or otherwise honor its obligations.
Schwab Opportunistic Municipal Bond Fund | Prepayment and Extension Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Prepayment and Extension Risk. Certain fixed-income securities are subject to the risk that the securities may be paid off earlier or later than expected, especially during periods of falling or rising interest rates, respectively. Prepayments of obligations could cause the fund to forgo future interest income on the portion of the security’s principal repaid early and force the fund to reinvest that money at the lower prevailing interest rates. Extensions of obligations could cause the fund to exhibit additional volatility and hold securities paying lower-than-market rates of interest. Either case could hurt the fund’s performance.
Schwab Opportunistic Municipal Bond Fund | Derivatives Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Derivatives Risk. The fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. The fund’s use of derivatives could reduce the fund’s performance, increase its volatility and cause the fund to lose more than the initial amount invested. In addition, investments in derivatives may involve leverage, which means a small percentage of assets invested in derivatives can have a disproportionately large impact on the fund.
Schwab Opportunistic Municipal Bond Fund | Liquidity Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Liquidity Risk. The fund may be unable to sell certain securities, such as illiquid securities, readily at a favorable time or price, or the fund may have to sell them at a loss.
Schwab Opportunistic Municipal Bond Fund | Portfolio Turnover Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Portfolio Turnover Risk. The fund buys and sells portfolio securities actively. This may cause the fund’s portfolio turnover rate and transaction costs to rise, which may lower the fund’s performance and may increase the likelihood of capital gains distributions.
Schwab Opportunistic Municipal Bond Fund | Management Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Management Risk. As an actively managed mutual fund, the fund is subject to the risk that its investment adviser will select investments or allocate assets in a manner that could cause the fund to underperform or otherwise not meet its investment objective. The fund’s investment adviser applies its own investment techniques and risk analyses in making investment decisions for the fund, but there can be no guarantee that they will produce the desired results.
Schwab Opportunistic Municipal Bond Fund | Municipal Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Municipal Securities Risk. The fund primarily invests in municipal securities whose interest, in the opinion of the issuers’ counsel, is exempt from federal income tax. Neither the investment adviser nor the fund guarantees that this opinion is correct, and there is no assurance that the Internal Revenue Service (IRS) will agree with such counsel’s opinion. If certain types of investments the fund buys as tax-exempt are later ruled to be taxable, a portion of the fund’s income could be taxable. To the extent that the fund invests in municipal securities from a given state or geographic region, its share price and performance could be affected by local, state and regional factors, including erosion of the tax base and changes in the economic climate. In addition, many municipal securities are issued to finance specific projects (especially those relating to education, health care, transportation and utilities) and conditions in those sectors can affect the overall municipal market. National governmental actions, such as the elimination of tax-exempt status or the reduction of financial support to municipalities, also could affect performance. Some municipalities continue to experience are experiencing difficulties in the current economic and political environment.
Schwab Opportunistic Municipal Bond Fund | High-Yield Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] High-Yield Risk. High-yield securities and unrated securities of similar credit quality (junk bonds) are subject to greater levels of credit and liquidity risks, and may be more volatile than higher-rated securities. High-yield securities are considered predominately speculative with respect to the issuer’s continuing ability to make principal and interest payments.
Schwab Opportunistic Municipal Bond Fund | Taxable Investments Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Taxable Investments Risk. The fund may invest a portion of its assets in securities that generate income that is not exempt from federal income tax and in securities whose interest is subject to the AMT. These investments could generate taxable income for shareholders.
Schwab Opportunistic Municipal Bond Fund | Distressed or Defaulted Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Distressed or Defaulted Securities Risk. Investments in defaulted securities and obligations of distressed issuers, including securities that are, or may be, involved in reorganizations or other financial restructurings, either out of court or in bankruptcy, involve substantial risks in addition to the risks of investing in high-yield debt securities. The fund’s share price may decline if the reorganization or restructuring is not completed as anticipated. The fund will generally not receive interest payments on the distressed securities and may incur costs to protect its investment. Repayment of defaulted securities and obligations of distressed issuers is subject to significant uncertainties. The fund could lose its entire investment in such securities.
Schwab Opportunistic Municipal Bond Fund | Rule 144A Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Rule 144A Securities Risk. The market for Rule 144A securities typically is less active than the market for publicly-traded securities. Rule 144A securities carry the risk that the liquidity of these securities may become impaired, making it more difficult for the fund to sell these bonds.
Schwab Opportunistic Municipal Bond Fund | Zero Coupon Securities Risk [Member]  
Prospectus [Line Items]  
Risk [Text Block] Zero Coupon Securities Risk. While interest payments are not made on such securities, holders of such securities are deemed to have received income annually, notwithstanding that cash may not be received currently. Some of these securities may be subject to substantially greater price fluctuations during periods of changing market interest rates than are comparable securities that pay interest currently. Longer term zero coupon bonds are more exposed to interest rate risk than shorter term zero coupon bonds.