Label	Element	Value
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	DFA Intermediate Government Fixed Income Portfolio
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The investment objective of the DFA Intermediate Government Fixed Income Portfolio (the “Intermediate Government Portfolio” or the “Portfolio”) is to earn current income consistent with preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Portfolio
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses you may pay if you buy, hold or sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	A fund generally pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 24% of the average value of its investment portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	24.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is meant to help you compare the cost of investing in the Portfolio with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs whether you redeem or hold your shares would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Intermediate Government Portfolio primarily invests in high quality, low-risk obligations of the U.S. Government and its agencies with maturities between five and fifteen years from the date of settlement. The Portfolio normally invests in non-callable obligations issued or guaranteed by the U.S. Government and U.S. government agencies, AAA-rated, dollar-denominated obligations of foreign governments, obligations of supranational organizations, and futures contracts on U.S. Treasury securities. Since government guaranteed mortgage-backed securities are considered callable, such securities will not be included in the Portfolio. Generally, the Intermediate Government Portfolio will purchase securities with maturities between five and fifteen years from the date of settlement. The Portfolio will not shift the maturity of its investments in anticipation of interest rate movements and ordinarily will have a weighted average maturity, based upon market values, between three and ten years. Under normal circumstances, when determining its duration, the Portfolio will consider a duration similar to the Bloomberg U.S. Government Bond Index, which was approximately 6.11 years as of December 31, 2023. In any event, as a non-fundamental policy, under normal circumstances, the Portfolio will invest at least 80% of its net assets in fixed income government securities and maintain a weighted average maturity between three and ten years. Duration is a measure of the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Intermediate Government Portfolio may invest a portion of its assets in the obligations of foreign governments. Those obligations at the time of purchase must be either rated in the highest rating category of a nationally recognized statistical rating organization or, in the case of any obligation that is unrated, of comparable quality. The Portfolio is authorized to invest more than 25% of its total assets in U.S. Treasury bonds, bills and notes and obligations of federal agencies and instrumentalities. The Portfolio may also invest in money market funds. The Portfolio also may purchase or sell futures contracts on U.S. Treasury securities or options on such contracts to increase or decrease market exposure based on actual or expected cash inflows to or outflows from the Portfolio. However, the Portfolio will not purchase or sell futures contracts or options thereon if as a result more than 5% of its net assets would then consist of initial margin deposits and premiums required to establish such positions. The Intermediate Government Portfolio may lend its portfolio securities to generate additional income.
Risk [Heading]	rr_RiskHeading	Principal Risks
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and table immediately following illustrate the variability of the Portfolio’s returns and are meant to provide some indication of the risks of investing in the Portfolio. The bar chart shows the changes in the Portfolio’s performance from year to year. The table illustrates how annualized returns for certain periods, both before and after taxes, compare with those of a broad measure of market performance. The Portfolio’s past performance (before and after taxes) is not an indication of future results. Updated performance information for the Portfolio can be obtained by visiting https://www.dimensional.com/us-en/funds. The after-tax returns presented in the table for the Portfolio are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown in the table. In addition, the after-tax returns shown are not relevant to investors who hold shares of the Portfolio through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and table immediately following illustrate the variability of the Portfolio’s returns and are meant to provide some indication of the risks of investing in the Portfolio. The bar chart shows the changes in the Portfolio’s performance from year to year.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	https://www.dimensional.com/us-en/funds
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Portfolio’s past performance (before and after taxes) is not an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	DFA Intermediate Government Fixed Income Portfolio Institutional Class Shares —Total Returns
Performance Table Heading	rr_PerformanceTableHeading	Annualized Returns (%)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	The after-tax returns presented in the table for the Portfolio are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	In addition, the after-tax returns shown are not relevant to investors who hold shares of the Portfolio through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Risk Lose Money [Member]
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Because the value of your investment in the Portfolio will fluctuate, there is the risk that you will lose money.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Risk Not Insured [Member]
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Market Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Market Risk: Even a long-term investment approach cannot guarantee a profit. Economic, political, and issuer-specific events will cause the value of securities, and a fund that owns them, to rise or fall.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Interest Rate Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Interest Rate Risk: Fixed income securities are subject to interest rate risk because the prices of fixed income securities tend to move in the opposite direction of interest rates. When interest rates rise, fixed income security prices fall. During periods of very low or negative interest rates, a fund may be subject to a greater risk of rising interest rates. When interest rates fall, fixed income security prices rise. In general, fixed income securities with longer maturities are more sensitive to changes in interest rates.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Credit Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Credit Risk: Credit risk is the risk that the issuer of a security may be unable to make interest payments and/or repay principal when due. A downgrade to an issuer’s credit rating or a perceived change in an issuer’s financial strength may affect a security’s value, and thus, impact the performance of a fund holding such securities. Government agency obligations have different levels of credit support and, therefore, different degrees of credit risk. Securities issued by agencies and instrumentalities of the U.S. Government that are supported by the full faith and credit of the United States, such as the Federal Housing Administration and Ginnie Mae, present little credit risk. Other securities issued by agencies and instrumentalities sponsored by the U.S. Government, that are supported only by the issuer’s right to borrow from the U.S. Treasury, subject to certain limitations, and securities issued by agencies and instrumentalities sponsored by the U.S. Government that are sponsored by the credit of the issuing agencies, such as Freddie Mac and Fannie Mae, are subject to a greater degree of credit risk. U.S. government agency securities issued or guaranteed by the credit of the agency may still involve a risk of non-payment of principal and/or interest.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Income Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Income Risk: Income risk is the risk that falling interest rates will cause a fund’s income to decline because, among other reasons, the proceeds from maturing short-term securities in its portfolio may be reinvested in lower-yielding securities.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Derivatives Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Derivatives Risk: Derivatives are instruments, such as futures contracts, and options thereon, whose value is derived from that of other assets, rates or indices. The use of derivatives for non-hedging purposes may be considered to carry more risk than other types of investments. When a fund uses derivatives, the fund will be directly exposed to the risks of those derivatives. Derivative instruments are subject to a number of risks including counterparty, liquidity, interest rate, market, credit and management risks, as well as the risk of improper valuation. Changes in the value of a derivative may not correlate perfectly with the underlying asset, rate or index, and a fund could lose more than the principal amount invested.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Liquidity Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Liquidity Risk: Liquidity risk exists when particular portfolio investments are difficult to purchase or sell. To the extent that a fund holds illiquid investments, the fund’s performance may be reduced due to an inability to sell the investments at opportune prices or times. Liquid portfolio investments may become illiquid or less liquid after purchase by a fund due to low trading volume, adverse investor perceptions and/or other market developments. Liquidity risk includes the risk that a fund will experience significant net redemptions at a time when it cannot find willing buyers for its portfolio securities or can only sell its portfolio securities at a material loss or at increased costs. Liquidity risk can be more pronounced in periods of market turmoil or in situations where ownership of shares of a fund are concentrated in one or a few investors.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Securities Lending Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Securities Lending Risk: Securities lending involves the risk that the borrower may fail to return the securities in a timely manner or at all. As a result, a fund may lose money and there may be a delay in recovering the loaned securities. A fund could also lose money if it does not recover the securities and/or the value of the collateral falls, including the value of investments made with cash collateral. Securities lending also may have certain adverse tax consequences.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Operational Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Operational Risk: Operational risks include human error, changes in personnel, system changes, faults in communication, and failures in systems, technology, or processes. Various operational events or circumstances are outside a fund’s or its advisor’s control, including instances at third parties. A fund and its advisor seek to reduce these operational risks through controls and procedures. However, measures that seek to reduce these operational risks through controls and procedures may not address every possible risk and may be inadequate to address these risks.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Cyber Security Risk
Risk/Return:	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Cyber Security Risk: A fund and its service providers’ use of internet, technology and information systems may expose the fund to potential risks linked to cyber security breaches of those technological or information systems. Cyber security breaches, amongst other things, could allow an unauthorized party to gain access to proprietary information, customer data, or fund assets, or cause the fund and/or its service providers to suffer data corruption or lose operational functionality.
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Bloomberg U.S. Government Bond Index
Risk/Return:	rr_RiskReturnAbstract
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	(reflects no deduction for fees, expenses or taxes)
Label	rr_AverageAnnualReturnLabel	Bloomberg U.S. Government Bond Index
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Bloomberg U.S. Government Bond Index
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	4.09%
5 Years	rr_AverageAnnualReturnYear05	0.56%
10 Years	rr_AverageAnnualReturnYear10	1.27%
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Management Fee	rr_ManagementFeesOverAssets	0.09%
Other Expenses	rr_OtherExpensesOverAssets	0.03%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.12%
1 Year	rr_ExpenseExampleYear01	$ 12
3 Years	rr_ExpenseExampleYear03	39
5 Years	rr_ExpenseExampleYear05	68
10 Years	rr_ExpenseExampleYear10	154
1 Year	rr_ExpenseExampleNoRedemptionYear01	12
3 Years	rr_ExpenseExampleNoRedemptionYear03	39
5 Years	rr_ExpenseExampleNoRedemptionYear05	68
10 Years	rr_ExpenseExampleNoRedemptionYear10	$ 154
Annual Return 2014	rr_AnnualReturn2014	5.18%
Annual Return 2015	rr_AnnualReturn2015	1.77%
Annual Return 2016	rr_AnnualReturn2016	1.15%
Annual Return 2017	rr_AnnualReturn2017	2.22%
Annual Return 2018	rr_AnnualReturn2018	0.92%
Annual Return 2019	rr_AnnualReturn2019	7.22%
Annual Return 2020	rr_AnnualReturn2020	9.10%
Annual Return 2021	rr_AnnualReturn2021	(3.15%)
Annual Return 2022	rr_AnnualReturn2022	(13.12%)
Annual Return 2023	rr_AnnualReturn2023	4.59%
Label	rr_HighestQuarterlyReturnLabel	Highest Quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Mar. 31, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	8.57%
Label	rr_LowestQuarterlyReturnLabel	Lowest Quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2022
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(5.98%)
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	4.59%
5 Years	rr_AverageAnnualReturnYear05	0.58%
10 Years	rr_AverageAnnualReturnYear10	1.40%
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Institutional Class \| After Taxes on Distributions
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	3.58%
5 Years	rr_AverageAnnualReturnYear05	(0.34%)
10 Years	rr_AverageAnnualReturnYear10	0.46%
Prospectus Summary \| DFA INTERMEDIATE GOVERNMENT FIXED INCOME PORTFOLIO \| Institutional Class \| After Taxes on Distributions and Sales
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions and Sale of Portfolio Shares
1 Year	rr_AverageAnnualReturnYear01	2.70%
5 Years	rr_AverageAnnualReturnYear05	0.15%
10 Years	rr_AverageAnnualReturnYear10	0.72%

If the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph ii