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Investment Objective

Expense Heading [Optional Text]

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Fees and Expenses

Shareholder Fees Caption [Optional Text]

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Shareholder Fees (fees paid directly from your investment)

Expenses Restated to Reflect Current [Text]

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Total Annual Fund Operating Expenses have been restated to reflect current expenses as of June 30, 2026.

Expense Example Narrative [Text Block]

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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 the reinvestment of all dividends and distributions in shares of the Portfolio, 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 [Text Block]

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The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in 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 19% of the average value of its portfolio.

Strategy [Heading]

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Principal Investment Strategies

Summary of Definition of Rule 35d-1 Term in Fund Name [Text Block]

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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. 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”). Municipal Securities purchased for the Portfolio will have varying maturities, but under normal circumstances the Portfolio will have an effective dollar weighted average portfolio maturity that is within the range of the average portfolio maturity in the Bloomberg 3‑10 Year Blend (2‑12) Total Return Index, currently 1 to 12 years. The Portfolio’s actual average maturity was 6.92 years as of June 30, 2026. Fixed income securities rated in the fourth highest rating category by a rating agency may have speculative characteristics.

Rule 35d-1 Eighty Percent Investment Policy [Text Block]

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Under normal circumstances, the Portfolio seeks to achieve its objective by investing primarily (i.e., at least 80% of net assets) in municipal bonds.

Performance Narrative [Text Block]

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Performance. The chart and table below show how The Intermediate 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 Past Does Not Indicate Future [Text]

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Of course, past performance, before and after taxes, does not indicate how the Portfolio will perform in the future.

Bar Chart Footnotes [Text Block]

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* Results shown on a calendar year basis; the Portfolio’s fiscal year, however, is June 30.

Year to Date Return, Label [Optional Text]

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before-tax return

Bar Chart, Year to Date Return

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(3.63%)

Highest Quarterly Return, Date

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Dec. 31, 2023

Lowest Quarterly Return, Label [Optional Text]

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Worst quarter:

Lowest Quarterly Return

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(5.26%)

Index No Deduction for Fees, Expenses, or Taxes [Text]

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(reflects no deduction for fees, expenses or taxes)

Performance Table Not Relevant to Tax Deferred

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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.

Risk [Text Block]

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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.

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Risk [Text Block]

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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.

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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.

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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.

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High Yield Bond Risk – High yield bonds, commonly referred to as “junk bonds,” are considered speculative under traditional investment standards. The prices of these securities will rise and fall primarily in response to changes in the issuer’s financial health. Change in market interest rates will also affect prices.

High yield bonds may also experience reduced liquidity, and sudden and substantial decreases in price, during certain market conditions.

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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.

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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.

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General Derivative Risks – Derivatives may be volatile and may involve significant risks. The Portfolio’s exposure to derivatives involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other investments. The underlying security, measure or other instrument on which a derivative is based, or the derivative itself, may not perform as expected, and hedging positions may not correlate closely with the instruments or exposures being hedged. Normally derivatives involve leverage, which means that their use can significantly magnify the effect of price movements of the underlying securities or reference measures, disproportionately increasing the Portfolio’s losses and reducing the Portfolio’s opportunities for gains. Some derivatives have the potential for unlimited loss, including a loss that may be greater than the amount invested. Derivatives also present default risks if the counterparty to a derivatives contract fails to fulfill its obligations to the Portfolio. Certain derivatives held by the Portfolio may be illiquid, including non-exchange-traded or over-the-counter derivatives that are linked to illiquid instruments or illiquid markets, making it difficult to close out an unfavorable position. Derivatives also may be more difficult to purchase, sell or value than other instruments. Derivatives risk may be more significant when derivatives are used to enhance return or as a substitute for a cash investment position, rather than solely to hedge the risk of a position held by the Portfolio.

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Derivatives Tax Risk – Compared to other types of investments, derivatives may be less tax efficient. In addition, changes in government regulation of derivative instruments could affect the character, timing and amount of the Portfolio’s taxable income or gains, and may limit or prevent the Portfolio’s use of certain derivative instruments, which could make the

investment strategy more costly to implement or require the Portfolio to change its investment strategy. These rules may: (i) affect whether gains and losses recognized by the Portfolio are treated as ordinary or capital or as short-term or long-term, (ii) accelerate the recognition of income or gains to the Portfolio, (iii) defer losses to the Portfolio, and (iv) cause adjustments in the holding periods of the Portfolio’s securities. The Portfolio’s use of derivatives may be limited by the requirements for taxation of the Portfolio as a regulated investment company.

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Options Writing Strategy Risk – if the underlying index appreciates or depreciates sufficiently over the period to offset the new premium received from the written option on that index, a net loss will result. In addition, the Portfolio may write options on index substitutes, which are subject to the same risks as index options. The value of the index substitute is subject to change as the values of the component securities fluctuate and the performance of the index substitute may not exactly match the performance of the index.

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