v3.26.3
Label Element Value
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk/Return [Heading] oef_RiskReturnHeading The Short-Term Municipal Bond Portfolio
Objective [Heading] oef_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] oef_ObjectivePrimaryTextBlock

The investment objective of The Short-Term Municipal Bond Portfolio is to provide a high level of current income exempt from Federal income tax, consistent with the preservation of capital.
Expense Heading [Optional Text] oef_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] oef_ExpenseNarrativeTextBlock

The fee and expense tables below describe the fees and expenses that you may pay if you buy and hold shares of the Portfolio.
Shareholder Fees Caption [Optional Text] oef_ShareholderFeesCaption Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Optional Text] oef_OperatingExpensesCaption Annual Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Expenses Restated to Reflect Current [Text] oef_ExpensesRestatedToReflectCurrent Total Annual Fund Operating Expenses have been restated to reflect current expenses as of June 30, 2026.
Expense Example [Heading] oef_ExpenseExampleHeading Example:
Expense Example Narrative [Text Block] oef_ExpenseExampleNarrativeTextBlock

  This Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s Total Annual Operating Expenses remain the same. Although your actual cost may be higher or lower, based on these assumptions, your cost would be:
Portfolio Turnover [Heading] oef_PortfolioTurnoverHeading Portfolio Turnover
Portfolio Turnover [Text Block] oef_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” investments in its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in the Total Annual Operating Expenses or in the Example, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover was 34% of the average value of its portfolio.
Portfolio Turnover, Rate oef_PortfolioTurnoverRate 34.00%
Strategy [Heading] oef_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] oef_StrategyNarrativeTextBlock

Under normal circumstances, the Portfolio seeks to achieve its objective by investing primarily (i.e. at least 80% of net assets) in municipal bonds. The policy stated in the foregoing sentence is a fundamental policy and may not be changed without shareholder approval. Municipal bonds are debt securities issued by municipalities and related entities, the interest on which is exempt from Federal income tax so that they will qualify to pay “exempt-interest dividends” (“Municipal Securities”). The Portfolio intends to maintain a dollar-weighted effective average portfolio maturity of no longer than three years. The Portfolio invests primarily in securities that are rated in one of the top four rating categories of a nationally recognized statistical rating organization (“Baa” or higher by Moody’s Investors Service, Inc., “BBB” or higher by S&P Global Ratings) or, if unrated, that are determined by the Specialist Manager to be of comparable quality. Fixed income securities rated in the fourth highest rating category by a rating agency may have speculative characteristics. The Portfolio does not currently intend to invest in obligations, the interest on which is a preference item for purposes of the Federal alternative minimum tax. The Portfolio may invest in securities issued by other investment companies, including ETFs, that invest in municipal bonds.

The Portfolio is authorized to operate on a multi-manager basis. This means that a single Portfolio may be managed by more than one Specialist Manager. The multi-manager structure is generally designed to provide investors access to broadly diversified investment styles. The Trust seeks to engage skilled Specialist Managers to provide a broad exposure to the relevant asset class and returns in excess of the Portfolio’s benchmark over time.
Summary of Definition of Rule 35d-1 Term in Fund Name [Text Block] fnd_NmRule35d1TermDfnSmryTextBlock Municipal bonds are debt securities issued by municipalities and related entities, the interest on which is exempt from Federal income tax so that they will qualify to pay “exempt-interest dividends” (“Municipal Securities”). The Portfolio intends to maintain a dollar-weighted effective average portfolio maturity of no longer than three years. The Portfolio invests primarily in securities that are rated in one of the top four rating categories of a nationally recognized statistical rating organization (“Baa” or higher by Moody’s Investors Service, Inc., “BBB” or higher by S&P Global Ratings) or, if unrated, that are determined by the Specialist Manager to be of comparable quality. Fixed income securities rated in the fourth highest rating category by a rating agency may have speculative characteristics. The Portfolio does not currently intend to invest in obligations, the interest on which is a preference item for purposes of the Federal alternative minimum tax. The Portfolio may invest in securities issued by other investment companies, including ETFs, that invest in municipal bonds.
Summary of Selection Criteria for Rule 35d-1 Term in Fund Name [Text Block] fnd_NmRule35d1TermSlctnCritSmryTextBlock The Portfolio is authorized to operate on a multi-manager basis. This means that a single Portfolio may be managed by more than one Specialist Manager. The multi-manager structure is generally designed to provide investors access to broadly diversified investment styles. The Trust seeks to engage skilled Specialist Managers to provide a broad exposure to the relevant asset class and returns in excess of the Portfolio’s benchmark over time.
Rule 35d-1 Eighty Percent Investment Policy [Text Block] fnd_NmRule35d1EightyPctInvstmntPlcyTextBlock Under normal circumstances, the Portfolio seeks to achieve its objective by investing primarily (i.e. at least 80% of net assets) in municipal bonds.
Bar Chart and Performance Table [Heading] oef_BarChartAndPerformanceTableHeading Performance Bar Chart and Table
Performance Narrative [Text Block] oef_PerformanceNarrativeTextBlock

Performance. The chart and table below show how The Short-Term Municipal Bond Portfolio has performed, and how its performance has varied from year to year. The bar chart shows returns on a before-tax basis and gives some indication of risk by showing changes in the Portfolio’s yearly performance for each of the last ten full calendar years. The table accompanying the bar chart compares the Portfolio’s performance over time on a before and after-tax basis to that of a broad based market index and an index that more closely reflects the investments of the Portfolio. Of course, past performance, before and after taxes, does not indicate how the Portfolio will perform in the future.
Performance Information Illustrates Variability of Returns [Text] oef_PerformanceInformationIllustratesVariabilityOfReturns The chart and table below show how The Short-Term Municipal Bond Portfolio has performed, and how its performance has varied from year to year. The bar chart shows returns on a before-tax basis and gives some indication of risk by showing changes in the Portfolio’s yearly performance for each of the last ten full calendar years.
Performance Past Does Not Indicate Future [Text] oef_PerformancePastDoesNotIndicateFuture Of course, past performance, before and after taxes, does not indicate how the Portfolio will perform in the future.
Bar Chart [Heading] oef_BarChartHeading Year-by-Year Total Returns as of 12/31*
Bar Chart Footnotes [Text Block] oef_BarChartFootnotesTextBlock

* Results shown on a calendar year basis; the Portfolio’s fiscal year, however, is June 30.
Bar Chart Closing [Text Block] oef_BarChartClosingTextBlock

The Portfolio’s before-tax return for the period from January 1, 2026 through September 30, 2026 (non-annualized) was ‑1.06%.

 

Best quarter:

 

4th Qtr. 2023

3.22%

 

 

Worst quarter:

 

1st Qtr. 2022

‑2.95%

 
Year to Date Return, Label [Optional Text] oef_YearToDateReturnLabel before-tax return
Bar Chart, Year to Date Return, Date oef_BarChartYearToDateReturnDate Sep. 30, 2026
Bar Chart, Year to Date Return oef_BarChartYearToDateReturn (1.06%)
Highest Quarterly Return, Label [Optional Text] oef_HighestQuarterlyReturnLabel Best quarter:
Highest Quarterly Return, Date oef_BarChartHighestQuarterlyReturnDate Dec. 31, 2023
Highest Quarterly Return oef_BarChartHighestQuarterlyReturn 3.22%
Lowest Quarterly Return, Label [Optional Text] oef_LowestQuarterlyReturnLabel Worst quarter:
Lowest Quarterly Return, Date oef_BarChartLowestQuarterlyReturnDate Mar. 31, 2022
Lowest Quarterly Return oef_BarChartLowestQuarterlyReturn (2.95%)
Performance Table Heading oef_PerformanceTableHeading Average Annual Total Returns (for the periods ended 12/31/25)
Index No Deduction for Fees, Expenses, or Taxes [Text] oef_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Performance Table Uses Highest Federal Rate oef_PerformanceTableUsesHighestFederalRate After-tax returns 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 oef_PerformanceTableNotRelevantToTaxDeferred Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold Portfolio shares through tax-advantaged arrangements, such as qualified retirement plans.
Performance Table Closing [Text Block] oef_PerformanceTableClosingTextBlock

After-tax returns 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, and after-tax returns shown are not relevant to investors who hold Portfolio shares through tax-advantaged arrangements, such as qualified retirement plans.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Risk Lose Money [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock There is no guarantee that the Portfolio will achieve its investment objective and, as is the case with any investment, you may lose money on your investment in the Portfolio.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Tax Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

•

Tax Risk – Changes in Federal tax laws or regulations could change the tax-exempt status of income from any or all of the Portfolio’s municipal securities. In addition, short-term capital gains and a portion of any gain attributable to bonds purchased at market discount will be treated as ordinary income for Federal tax purposes.

Additionally, the range of securities in which the Portfolio may invest, and the several investment strategies that may be used in seeking to achieve the Portfolio’s objective, involve additional risks. These are summarized below.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Fixed Income Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

•

Fixed Income Risk.  Investments in fixed income securities may involve the following risks, depending on the instrument involved:
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Credit Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

•

Credit Risk – An investment in the Portfolio also involves the risk that the issuer of a fixed income security that the Portfolio holds will fail to make timely payments of interest or principal, or go bankrupt, or that the value of the securities will decline because of a market perception that the issuer may not make payments on time, thus potentially reducing the Portfolio’s return. Changes in economic conditions are likely to cause issuers of these fixed income securities to be unable to meet their obligations. The lower the rating of a debt security, the higher its credit risk. In addition, the securities of many U.S. Government agencies, authorities or instrumentalities in which the Portfolio may invest are neither issued nor guaranteed by the U.S. Government, and may be supported only by the ability of the issuer to borrow from the U.S. Treasury or by the credit of the issuer.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Interest Rate Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

•

Interest Rate Risk – The value of fixed income securities held in the Portfolio, including U.S. Government securities, may decline with changes in interest rates. Prices of fixed income securities with longer effective maturities are more sensitive to interest rate changes than those with shorter effective maturities.

U.S. Government securities can exhibit price movements resulting from changes in interest rates. During low interest rate environments, the risk that interest rates will rise is increased. Such increases may expose fixed income markets to heightened volatility and reduced liquidity for certain fixed income investments, particularly those with longer maturities. These risks are greater when a low interest rate environment has existed for an extended period of time.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Call/Prepayment Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

•

Call/Prepayment Risk – Municipal securities held by the Portfolio may be called (prepaid) before their maturity dates. This usually occurs as interest rates are declining. As a result of this risk, the Portfolio may have to reinvest these prepayments at those lower rates, thus reducing its income. In addition, the Portfolio may lose price appreciation if a bond it holds is called earlier than scheduled.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Extension Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

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Extension Risk – These securities are also subject to the risk that payment on the loans underlying the securities held by the Portfolio will be made more slowly when interest rates are rising. This could cause the market value of the securities to decline.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Municipal Bond Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

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Municipal Bond Risk – The risk of a municipal obligation generally depends on the financial and credit status of the issuer. Constitutional amendments, legislative enactments, executive orders, administrative regulations, voter initiatives, and the issuer’s regional economic conditions may affect the municipal security’s value, interest payments, repayment of principal and the Portfolio’s ability to sell the security. Failure of a municipal security issuer to comply with applicable tax requirements may make income paid thereon taxable, resulting in a decline in the security’s value. In addition, there could be changes in applicable tax laws or tax treatments that reduce or eliminate the current federal income tax exemption on municipal securities or otherwise adversely affect the current federal or state tax status of municipal securities.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Investment in Other Investment Companies Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

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Investment in Other Investment Companies Risk – As with other investments, investments in other investment companies are subject to market and selection risk. To the extent that the Portfolio acquires shares of investment companies, shareholders bear both their proportionate share of expenses in the Portfolio (including management and advisory fees) and, indirectly, the expenses of the acquired investment companies.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | Exchange-Traded Funds Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

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Exchange-Traded Funds Risk – In addition to the risks of investing in other investment companies generally, an investment in securities issued by an ETF may be subject to the following risks: (1) shares

of the ETF may trade at a discount to its net asset value; (2) an active trading market for the ETF’s shares may not develop; (3) the exchange on which the ETF is listed may, under certain circumstances, suspend trading of the ETF’s shares; and (4) to the extent that an ETF is acquired in order to track a specific asset or index, the ETF may fail to effectively accomplish that goal.
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio  
Prospectus [Line Items] oef_ProspectusLineItems  
Maximum Deferred Sales Charge (as a percentage of Offering Price) oef_MaximumDeferredSalesChargeOverOfferingPrice 0.00%
Redemption Fee (as a percentage of Amount Redeemed) oef_RedemptionFeeOverRedemption 0.00%
Management Fees (as a percentage of Assets) oef_ManagementFeesOverAssets 0.13%
Other Expenses (as a percentage of Assets): oef_OtherExpensesOverAssets 0.17%
Expenses (as a percentage of Assets) oef_ExpensesOverAssets 0.30% [1]
Expense Example, with Redemption, 1 Year oef_ExpenseExampleYear01 $ 31
Expense Example, with Redemption, 3 Years oef_ExpenseExampleYear03 97
Expense Example, with Redemption, 5 Years oef_ExpenseExampleYear05 169
Expense Example, with Redemption, 10 Years oef_ExpenseExampleYear10 $ 381
The Short-Term Municipal Bond Portfolio | Bloomberg 1‑3 Year Municipal Bond Index (reflects no deduction for fees, expenses or taxes)  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 3.66%
Average Annual Return, Percent oef_AvgAnnlRtrPct 3.17%
Average Annual Return, Percent oef_AvgAnnlRtrPct 1.58%
The Short-Term Municipal Bond Portfolio | Bloomberg Municipal Bond Index (reflects no deduction for fees, expenses or taxes)  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 4.25%
Average Annual Return, Percent oef_AvgAnnlRtrPct 3.88%
Average Annual Return, Percent oef_AvgAnnlRtrPct 2.34%
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio  
Prospectus [Line Items] oef_ProspectusLineItems  
Annual Return [Percent] oef_AnnlRtrPct (0.06%)
Annual Return [Percent] oef_AnnlRtrPct 0.86%
Annual Return [Percent] oef_AnnlRtrPct 1.45%
Annual Return [Percent] oef_AnnlRtrPct 3.01%
Annual Return [Percent] oef_AnnlRtrPct 2.18%
Annual Return [Percent] oef_AnnlRtrPct (0.15%)
Annual Return [Percent] oef_AnnlRtrPct (2.77%)
Annual Return [Percent] oef_AnnlRtrPct 3.07%
Annual Return [Percent] oef_AnnlRtrPct 1.60%
Annual Return [Percent] oef_AnnlRtrPct 3.59%
Average Annual Return, Percent oef_AvgAnnlRtrPct 3.59%
Average Annual Return, Percent oef_AvgAnnlRtrPct 1.04%
Average Annual Return, Percent oef_AvgAnnlRtrPct 1.26%
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | After Taxes on Distributions  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 3.56%
Average Annual Return, Percent oef_AvgAnnlRtrPct 1.00%
Average Annual Return, Percent oef_AvgAnnlRtrPct 1.23%
The Short-Term Municipal Bond Portfolio | The Short-Term Municipal Bond Portfolio | After Taxes on Distributions and Sales  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 3.17%
Average Annual Return, Percent oef_AvgAnnlRtrPct 1.18%
Average Annual Return, Percent oef_AvgAnnlRtrPct 1.29%
[1] Total Annual Fund Operating Expenses have been restated to reflect current expenses as of June 30, 2026.