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N-2 - USD ($) |  | 3 Months Ended
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Sep. 17, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023
Cover [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Entity Central Index Key |  | 0000832327 |  |  |  |  |  |  |  |  |  |
Amendment Flag |  | false |  |  |  |  |  |  |  |  |  |
Entity Inv Company Type |  | N-2 |  |  |  |  |  |  |  |  |  |
Securities Act File Number |  | 333-288158 |  |  |  |  |  |  |  |  |  |
Investment Company Act File Number |  | 811-05542 |  |  |  |  |  |  |  |  |  |
Document Type |  | N-2/A |  |  |  |  |  |  |  |  |  |
Document Registration Statement |  | true |  |  |  |  |  |  |  |  |  |
Pre-Effective Amendment |  | true |  |  |  |  |  |  |  |  |  |
Pre-Effective Amendment Number |  | 1 |  |  |  |  |  |  |  |  |  |
Post-Effective Amendment |  | false |  |  |  |  |  |  |  |  |  |
Investment Company Act Registration |  | true |  |  |  |  |  |  |  |  |  |
Investment Company Registration Amendment |  | true |  |  |  |  |  |  |  |  |  |
Investment Company Registration Amendment Number |  | 14 |  |  |  |  |  |  |  |  |  |
Entity Registrant Name |  | BlackRock Income Trust, Inc. |  |  |  |  |  |  |  |  |  |
Entity Address, Address Line One |  | 100 Bellevue Parkway |  |  |  |  |  |  |  |  |  |
Entity Address, City or Town |  | Wilmington |  |  |  |  |  |  |  |  |  |
Entity Address, State or Province |  | DE |  |  |  |  |  |  |  |  |  |
Entity Address, Postal Zip Code |  | 19809 |  |  |  |  |  |  |  |  |  |
City Area Code |  | 800 |  |  |  |  |  |  |  |  |  |
Local Phone Number |  | 882-0052 |  |  |  |  |  |  |  |  |  |
Approximate Date of Commencement of Proposed Sale to Public |  | From time to time after the effective date of this Registration Statement. |  |  |  |  |  |  |  |  |  |
Dividend or Interest Reinvestment Plan Only |  | false |  |  |  |  |  |  |  |  |  |
Delayed or Continuous Offering |  | true |  |  |  |  |  |  |  |  |  |
Primary Shelf [Flag] |  | true |  |  |  |  |  |  |  |  |  |
Effective Upon Filing, 462(e) |  | false |  |  |  |  |  |  |  |  |  |
Additional Securities Effective, 413(b) |  | false |  |  |  |  |  |  |  |  |  |
Effective when Declared, Section 8(c) |  | false |  |  |  |  |  |  |  |  |  |
New Effective Date for Previous Filing |  | false |  |  |  |  |  |  |  |  |  |
Additional Securities. 462(b) |  | false |  |  |  |  |  |  |  |  |  |
No Substantive Changes, 462(c) |  | false |  |  |  |  |  |  |  |  |  |
Exhibits Only, 462(d) |  | false |  |  |  |  |  |  |  |  |  |
Registered Closed-End Fund [Flag] |  | true |  |  |  |  |  |  |  |  |  |
Business Development Company [Flag] |  | false |  |  |  |  |  |  |  |  |  |
Interval Fund [Flag] |  | false |  |  |  |  |  |  |  |  |  |
Primary Shelf Qualified [Flag] |  | true |  |  |  |  |  |  |  |  |  |
Entity Well-known Seasoned Issuer |  | No |  |  |  |  |  |  |  |  |  |
Entity Emerging Growth Company |  | false |  |  |  |  |  |  |  |  |  |
New CEF or BDC Registrant [Flag] |  | false |  |  |  |  |  |  |  |  |  |
Fee Table [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Shareholder Transaction Expenses [Table Text Block] |  |
Shareholder Transaction Expenses |  |  |  |
Sales load paid by you (as a percentage of offering price) (1) |  |  | 1.00% |
Offering expenses borne by the Fund (as a percentage of offering price) (1) |  |  | 0.07% |
Dividend reinvestment plan fees |  |  | $0.02 per share for open-market purchases of common shares (2) |
Dividend reinvestment plan sale transaction fee |  |  | $2.50 (2) |
Estimated Annual Expenses (as a percentage of net assets attributable to common shares) |  |  |  |
Management Fees (3)(4) |  |  | 0.65% |
Other Expenses (5) |  |  | 2.10% |
Miscellaneous Other Expenses |  |  | 0.29% |
Interest Expense (6) |  |  | 1.81% |
Total Annual Fund Operating Expenses |  |  | 2.75% |
Fee Waivers and/or Expense Reimbursements (4) |  |  | --% |
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (4) |  |  | 2.75% |
(1) | If the common shares are sold to or through underwriters, the Prospectus Supplement will set forth any applicable sales load and the estimated offering expenses . Fund shareholders will pay all offering expenses involved with an offering.
(2) | The Reinvestment Plan Agent’s (as defined below under “Dividend Reinvestment Plan”) fees for the handling of the reinvestment of dividends will be paid by the Fund. However, you will pay a $0.02 per share fee incurred in connection with open-market purchases, which will be deducted from the value of the dividend. You will also be charged a $2.50 sales fee and pay a $0.15 per share fee if you direct the Reinvestment Plan Agent to sell your common shares held in a dividend reinvestment account. Per share fees include any applicable brokerage commissions the Reinvestment Plan Agent is required to pay.
Sales Load [Percent] | [1] | 1.00% |  |  |  |  |  |  |  |  |  |
Dividend Reinvestment and Cash Purchase Fees | [2] | $ 2.5 |  |  |  |  |  |  |  |  |  |
Other Transaction Expenses [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Other Transaction Expenses [Percent] | [1] | 0.07% |  |  |  |  |  |  |  |  |  |
Annual Expenses [Table Text Block] |  |
(3) | The Fund currently pays the Advisor a monthly fee at an annual contractual investment management fee rate of 0.65% of the average weekly value of the Fund’s Net Assets. “Net Assets” means the total assets of the Fund minus the sum of its accrued liabilities (including the aggregate indebtedness constituting financial leverage).
(4) | The Fund and the Advisor have entered into a fee waiver agreement (the “Fee Waiver Agreement”), pursuant to which the Advisor has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets attributable to investments in any equity and fixed-income mutual funds and exchange-traded funds (“ETFs”) managed by the Advisor or its affiliates and other exchange-traded products sponsored by the Advisor or its affiliates, in each case that have a contractual management fee, through June 30, 2027. In addition, pursuant to the Fee Waiver Agreement, the Advisor has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to the Advisor indirectly through its investment in money market funds managed by the Advisor or its affiliates, through June 30, 2027. The Fee Waiver Agreement may be terminated at any time, without the payment of any penalty, only by the Fund (upon the vote of a majority of the Directors who are not “interested persons” (as defined in the Investment Company Act) of the Fund (the “Independent Directors”) or a majority of the outstanding voting securities of the Fund), upon 90 days’ written notice by the Fund to the Advisor.
(5) | “Other Expenses” have been restated to reflect current Acquired Fund Fees and Expenses, which are less than 0.01%.
(6) | Assumes the use of leverage in the form of reverse repurchase agreements representing 25.6% of Managed Assets at an annual interest expense to the Fund of 5.29% which is based on current market conditions. The actual amount of interest expense borne by the Fund will vary over time in accordance with the level of the Fund’s use of reverse repurchase agreements and variations in market interest rates. Interest expense is required to be treated as an expense of the Fund for accounting purposes.
Management Fees [Percent] | [3],[4] | 0.65% |  |  |  |  |  |  |  |  |  |
Other Annual Expenses [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Other Annual Expense 1 [Percent] |  | 0.29% |  |  |  |  |  |  |  |  |  |
Other Annual Expense 2 [Percent] | [5] | 1.81% |  |  |  |  |  |  |  |  |  |
Other Annual Expenses [Percent] | [6] | 2.10% |  |  |  |  |  |  |  |  |  |
Total Annual Expenses [Percent] |  | 2.75% |  |  |  |  |  |  |  |  |  |
Waivers and Reimbursements of Fees [Percent] | [3] | 0.00% |  |  |  |  |  |  |  |  |  |
Net Expense over Assets [Percent] | [3] | 2.75% |  |  |  |  |  |  |  |  |  |
Expense Example [Table Text Block] |  | The following example illustrates the expenses (including the sales load of $10.00 and offering costs of $0.68) that you would pay on a $1,000 investment in common shares, assuming (i) total net annual expenses of 2.75% of net assets attributable to common shares, and (ii) a 5% annual return:
|  | One Year |  | Three Years |  | Five Years |  | Ten Years
Total expenses incurred |  | $38 |  | $95 |  | $155 |  | $315
Expense Example, Year 01 |  | $ 38 |  |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 3 |  | 95 |  |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 5 |  | 155 |  |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 10 |  | $ 315 |  |  |  |  |  |  |  |  |  |
Purpose of Fee Table , Note [Text Block] |  | The following example illustrates the expenses (including the sales load of $10.00 and offering costs of $0.68) that you would pay on a $1,000 investment in common shares, assuming (i) total net annual expenses of 2.75% of net assets attributable to common shares, and (ii) a 5% annual return: |  |  |  |  |  |  |  |  |  |
Basis of Transaction Fees, Note [Text Block] |  | as a percentage of offering price |  |  |  |  |  |  |  |  |  |
Other Transaction Fees, Note [Text Block] |  | If the common shares are sold to or through underwriters, the Prospectus Supplement will set forth any applicable sales load and the estimated offering expenses . Fund shareholders will pay all offering expenses involved with an offering. |  |  |  |  |  |  |  |  |  |
Other Expenses, Note [Text Block] |  | “Other Expenses” have been restated to reflect current Acquired Fund Fees and Expenses, which are less than 0.01%. |  |  |  |  |  |  |  |  |  |
Management Fee not based on Net Assets, Note [Text Block] |  |
(3) | The Fund currently pays the Advisor a monthly fee at an annual contractual investment management fee rate of 0.65% of the average weekly value of the Fund’s Net Assets. “Net Assets” means the total assets of the Fund minus the sum of its accrued liabilities (including the aggregate indebtedness constituting financial leverage).
(4) | The Fund and the Advisor have entered into a fee waiver agreement (the “Fee Waiver Agreement”), pursuant to which the Advisor has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets attributable to investments in any equity and fixed-income mutual funds and exchange-traded funds (“ETFs”) managed by the Advisor or its affiliates and other exchange-traded products sponsored by the Advisor or its affiliates, in each case that have a contractual management fee, through June 30, 2027. In addition, pursuant to the Fee Waiver Agreement, the Advisor has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to the Advisor indirectly through its investment in money market funds managed by the Advisor or its affiliates, through June 30, 2027. The Fee Waiver Agreement may be terminated at any time, without the payment of any penalty, only by the Fund (upon the vote of a majority of the Directors who are not “interested persons” (as defined in the Investment Company Act) of the Fund (the “Independent Directors”) or a majority of the outstanding voting securities of the Fund), upon 90 days’ written notice by the Fund to the Advisor.
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Investment Objectives and Practices [Text Block] |  | Investment Objective and Policies Please refer to the section of the Fund’s most recent annual report on Form N-CSR entitled “Investment Objectives, Policies and Risks—Investment Objectives and Policies—BlackRock Income Trust, Inc.” , which is incorporated by reference herein, for a discussion of the Fund’s investment objective and policies. Portfolio Contents and Techniques The Fund’s portfolio will be composed principally of the following investments. Additional information with respect to the Fund’s investment policies and restrictions and certain of the Fund’s portfolio investments is contained in the SAI. Mortgage Related Securities. Mortgage-Backed Securities . Mortgage-backed securities (“MBS”) include structured debt obligations collateralized by pools of commercial (“CMBS”) or residential (“RMBS”) mortgages. Pools of mortgage loans and mortgage-backed loans, such as mezzanine loans, are assembled as securities for sale to investors by various governmental, government-related and private organizations. MBS include complex instruments such as collateralized mortgage obligations (“CMOs”), stripped MBS, mortgage pass-through securities and interests in real estate mortgage investment conduits (“REMICs”). The MBS in which the Fund may invest include those with fixed, floating or variable interest rates, those with interest rates that change based on multiples of changes in a specified reference interest rate or index of interest rates and those with interest rates that change inversely to changes in interest rates, as well as those that do not bear interest. The Fund may invest in RMBS and CMBS issued by governmental entities and private issuers, including subordinated MBS and residual interests. The Fund may invest in sub-prime mortgages or MBS that are backed by sub-prime mortgages. In general, losses on a mortgaged property securing a mortgage loan included in a securitization will be borne first by the equity holder of the property, then by a cash reserve fund or letter of credit, if any, then by the holder of a mezzanine loan or B-Note, if any, then by the “first loss” subordinated security holder (generally, the “B-Piece” buyer) and then by the holder of a higher rated security. The Fund may invest in any class of security included in a securitization. In the event of default and the exhaustion of any equity support, reserve fund, letter of credit, mezzanine loans or B-Notes, and any classes of securities junior to those in which the Fund invests, the Fund will not be able to recover all of its investment in the MBS it purchases. MBS in which the Fund invests may not contain reserve funds, letters of credit, mezzanine loans and/or junior classes of securities. The prices of lower credit quality securities are generally less sensitive to interest rate changes than more highly rated investments, but more sensitive to adverse economic downturns or individual issuer developments. Mortgage Pass-Through Securities . Mortgage pass-through securities differ from other forms of fixed-income securities, which normally provide for periodic payment of interest in fixed amounts with principal payments at maturity or specified call dates. Instead, these securities provide a monthly payment which consists of both interest and principal payments. In effect, these payments are a “pass through” of the monthly payments made by the individual borrowers on their residential or commercial mortgage loans, net of any fees paid to the issuer or guarantor of such securities. Additional payments are caused by repayments of principal resulting from the sale of the underlying property, refinancing or foreclosure, net of fees or costs that may be incurred. Some mortgage related securities (such as securities issued by the Government National Mortgage Association (“GNMA”)) are described as “modified pass-through.” These securities entitle the holder to receive all interest and principal payments owed on the mortgage pool, net of certain fees, at the scheduled payment dates regardless of whether or not the mortgagor actually makes the payment. RMBS . RMBS are securities the payments on which depend primarily on the cash flow from residential mortgage loans made to borrowers that are secured on a first priority basis or second priority basis, subject to permitted liens, easements and other encumbrances by residential real estate (one- to four-family properties), the proceeds of which are used to purchase real estate and purchase or construct dwellings thereon or to refinance indebtedness previously used for such purposes. Non-agency residential mortgage loans are obligations of the borrowers thereunder only and are not typically insured or guaranteed by any other person or entity. The ability of a borrower to repay a loan secured by residential property is dependent upon the income or assets of the borrower. A number of factors, including a general economic downturn, acts of God, terrorism, social unrest and civil disturbances, may impair a borrower’s ability to repay its loans. Agency RMBS . The principal U.S. Governmental guarantor of mortgage related securities is GNMA, which is a wholly owned U.S. Government corporation. GNMA is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA (such as savings and loan institutions, commercial banks and mortgage bankers) and backed by pools of mortgages insured by the Federal Housing Administration (“FHA”), or guaranteed by the Department of Veterans Affairs (“VA”). MBS issued by GNMA include GNMA Mortgage Pass-Through Certificates (also known as “Ginnie Maes”) which are guaranteed as to the timely payment of principal and interest by GNMA and such guarantees are backed by the full faith and credit of the United States. GNMA certificates also are supported by the authority of GNMA to borrow funds from the U.S. Treasury to make payments under its guarantee. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). FNMA is a government-sponsored corporation the common stock of which is owned entirely by private stockholders. FNMA purchases conventional (i.e., not insured or guaranteed by any government agency) residential mortgages from a list of approved seller/servicers which include state and federally chartered savings and loan associations, mutual savings banks, commercial banks and credit unions and mortgage bankers. Pass-through securities issued by FNMA (also known as “Fannie Maes”) are guaranteed as to timely payment of principal and interest by FNMA, but are not backed by the full faith and credit of the U.S. Government. FHLMC was created by Congress in 1970 for the purpose of increasing the availability of mortgage credit for residential housing. It is a government-sponsored corporation that issues FHLMC Guaranteed Mortgage Pass-Through Certificates (also known as “Freddie Macs” or “PCs”), which are pass-through securities, each representing an undivided interest in a pool of residential mortgages. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but PCs are not backed by the full faith and credit of the U.S. Government. In 2008, the Federal Housing Finance Agency (“FHFA”) placed FNMA and FHLMC into conservatorship. FNMA and FHLMC are continuing to operate as going concerns while in conservatorship and each remains liable for all of its obligations, including its guaranty obligations, associated with its MBS. As the conservator, FHFA succeeded to all rights, titles, powers and privileges of FNMA and FHLMC and of any stockholder, officer or director of FNMA and FHLMC with respect to FNMA and FHLMC and the assets of FNMA and FHLMC. In connection with the conservatorship, the U.S. Treasury entered into a Senior Preferred Stock Purchase Agreement with each of FNMA and FHLMC pursuant to which the U.S. Treasury would purchase up to an aggregate of $100 billion of each of FNMA and FHLMC to maintain a positive net worth in each enterprise. This agreement contains various covenants that severely limit each enterprise’s operations. In exchange for entering into these agreements, the U.S. Treasury received $1 billion of each enterprise’s senior preferred stock and warrants to purchase 79.9% of each enterprise’s common stock. In February 2009, the U.S. Treasury doubled the size of its commitment to each enterprise under the Senior Preferred Stock Program to $200 billion. The U.S. Treasury’s obligations under the Senior Preferred Stock Program are for an indefinite period of time for a maximum amount of $200 billion per enterprise. In December 2009, the U.S. Treasury announced further amendments to the Senior Preferred Stock Purchase Agreements which included additional financial support to certain governmentally supported entities, including the Federal Home Loan Banks (“FHLBs”), FNMA and FHLMC. It is difficult, if not impossible, to predict the future political, regulatory or economic changes that could impact FNMA, FHLMC and the FHLBs, and the values of their related securities or obligations. There is no assurance that the obligations of such entities will be satisfied in full, or that such obligations will not decrease in value or default. Under the Federal Housing Finance Regulatory Reform Act of 2008 (the “Reform Act”), which was included as part of the Housing and Economic Recovery Act of 2008, FHFA, as conservator or receiver, has the power to repudiate any contract entered into by FNMA or FHLMC prior to FHFA’s appointment as conservator or receiver, as applicable, if FHFA determines, in its sole discretion, that performance of the contract is burdensome and that repudiation of the contract promotes the orderly administration of FNMA’s or FHLMC’s affairs. The Reform Act requires FHFA to exercise its right to repudiate any contract within a reasonable period of time after its appointment as conservator or receiver. FHFA, in its capacity as conservator, has indicated that it has no intention to repudiate the guaranty obligations of FNMA or FHLMC because FHFA views repudiation as incompatible with the goals of the conservatorship. However, in the event that FHFA, as conservator or if it is later appointed as receiver for FNMA or FHLMC, were to repudiate any such guaranty obligation, the conservatorship or receivership estate, as applicable, would be liable for actual direct compensatory damages in accordance with the provisions of the Reform Act. Any such liability could be satisfied only to the extent of FNMA’s or FHLMC’s assets available therefor. In the event of repudiation, the payments of interest to holders of FNMA or FHLMC MBS would be reduced if payments on the mortgage loans represented in the mortgage loan groups related to such MBS are not made by the borrowers or advanced by the servicer. Any actual direct compensatory damages for repudiating these guaranty obligations may not be sufficient to offset any shortfalls experienced by such mortgage-backed security holders. Further, in its capacity as conservator or receiver, FHFA has the right to transfer or sell any asset or liability of FNMA or FHLMC without any approval, assignment or consent. Although FHFA has stated that it has no present intention to do so, if FHFA, as conservator or receiver, were to transfer any such guaranty obligation to another party, holders of FNMA or FHLMC MBS would have to rely on that party for satisfaction of the guaranty obligation and would be exposed to the credit risk of that party. In addition, certain rights provided to holders of MBS issued by FNMA and FHLMC under the operative documents related to such securities may not be enforced against FHFA, or enforcement of such rights may be delayed, during the conservatorship or any future receivership. The operative documents for FNMA and FHLMC MBS may provide (or with respect to securities issued prior to the date of the appointment of the conservator may have provided) that upon the occurrence of an event of default on the part of FNMA or FHLMC, in its capacity as guarantor, which includes the appointment of a conservator or receiver, holders of such MBS have the right to replace FNMA or FHLMC as trustee if the requisite percentage of MBS holders consent. The Reform Act prevents mortgage-backed security holders from enforcing such rights if the event of default arises solely because a conservator or receiver has been appointed. Non-Agency RMBS . Non-agency RMBS are issued by commercial banks, savings and loan institutions, mortgage bankers, private mortgage insurance companies and other non-governmental issuers. Timely payment of principal and interest on RMBS backed by pools created by non-governmental issuers often is supported partially by various forms of insurance or guarantees, including individual loan, title, pool and hazard insurance. The insurance and guarantees are issued by government entities, private insurers and the mortgage poolers. There can be no assurance that the private insurers or mortgage poolers can meet their obligations under the policies, so that if the issuers default on their obligations, the holders of the security could sustain a loss. No insurance or guarantee covers the Fund or the price of the Fund’s common shares. RMBS issued by non-governmental issuers generally offer a higher rate of interest than government agency and government-related securities because there are no direct or indirect government guarantees of payment. CMBS . CMBS generally are multi-class debt or pass-through certificates secured or backed by mortgage loans on commercial properties. CMBS generally are structured to provide protection to the senior class investors against potential losses on the underlying mortgage loans. This protection generally is provided by having the holders of subordinated classes of securities (“Subordinated CMBS”) take the first loss if there are defaults on the underlying commercial mortgage loans. Other protection, which may benefit all of the classes or particular classes, may include issuer guarantees, reserve funds, additional Subordinated CMBS, cross-collateralization and over-collateralization. The Fund may invest in Subordinated CMBS, which are subordinated in some manner as to the payment of principal and/or interest to the holders of more senior CMBS arising out of the same pool of mortgages and which are often referred to as “B-Pieces.” The holders of Subordinated CMBS typically are compensated with a higher stated yield than are the holders of more senior CMBS. On the other hand, Subordinated CMBS typically subject the holder to greater risk than senior CMBS and tend to be rated in a lower rating category (frequently a substantially lower rating category) than the senior CMBS issued in respect of the same mortgage pool. Subordinated CMBS generally are likely to be more sensitive to changes in prepayment and interest rates and the market for such securities may be less liquid than is the case for traditional income securities and senior CMBS. CMOs . A CMO is a multi-class bond backed by a pool of mortgage pass-through certificates or mortgage loans. CMOs may be collateralized by (i) GNMA, FNMA or FHLMC pass-through certificates, (ii) unsecuritized mortgage loans insured by the FHA or guaranteed by the VA, (iii) unsecuritized conventional mortgages, (iv) other MBS or (v) any combination thereof. Each class of a CMO, often referred to as a “tranche,” is issued at a specific coupon rate and has a stated maturity or final distribution date. Principal prepayments on collateral underlying a CMO may cause it to be retired substantially earlier than its stated maturity or final distribution date. The principal and interest on the underlying mortgages may be allocated among the several classes of a series of a CMO in many ways. One or more tranches of a CMO may have coupon rates which reset periodically at a specified increment over an index, such as the Secured Overnight Financing Rate (“SOFR”) (or sometimes more than one index). These floating rate CMOs typically are issued with lifetime caps on the coupon rate thereon. The Fund does not intend to invest in CMO residuals, which represent the interest in any excess cash flow remaining after making the payments of interest and principal on the tranches issued by the CMO and the payment of administrative expenses and management fees. The Fund may invest in inverse floating rate CMOs. Inverse floating rate CMOs constitute a tranche of a CMO with a coupon rate that moves in the reverse direction relative to an applicable index such as SOFR. Accordingly, the coupon rate thereon will increase as interest rates decrease. Inverse floating rate CMOs are typically more volatile than fixed or floating rate tranches of CMOs. Many inverse floating rate CMOs have coupons that move inversely to a multiple of an index. The effect of the coupon varying inversely to a multiple of an applicable index creates a leverage factor. Inverse floating rate debt instruments (“inverse floaters”) based on multiples of a stated index are designed to be highly sensitive to changes in interest rates and can subject the holders thereof to extreme reductions of yield and loss of principal. The market for inverse floating rate CMOs with highly leveraged characteristics at times may be very thin. The Fund’s ability to dispose of its positions in such securities will depend on the degree of liquidity in the markets for such securities. It is impossible to predict the amount of trading interest that may exist in such securities, and therefore the future degree of liquidity. Stripped MBS . Stripped MBS are created by segregating the cash flows from underlying mortgage loans or mortgage securities to create two or more new securities, each receiving a specified percentage of the underlying security’s principal or interest payments. Mortgage securities may be partially stripped so that each investor class receives some interest and some principal. When securities are completely stripped, however, all of the interest is distributed to holders of one type of security, known as an interest-only security (or “IO”), and all of the principal is distributed to holders of another type of security, known as a principal-only security (or “PO”). Strips can be created in a pass-through structure or as tranches of a CMO. The yields to maturity on IOs and POs are very sensitive to the rate of principal payments (including prepayments) on the related underlying mortgage assets. If the underlying mortgage assets experience greater than anticipated prepayments of principal, the Fund may not fully recoup its initial investment in IOs. Conversely, if the underlying mortgage assets experience less than anticipated prepayments of principal, the yield on POs could be materially and adversely affected. Adjustable Rate Mortgage Securities . Adjustable rate mortgages (“ARMs”) have interest rates that reset at periodic intervals. Acquiring ARMs permits the Fund to participate in increases in prevailing current interest rates through periodic adjustments in the coupons of mortgages underlying the pool on which ARMs are based. Such ARMs generally have higher current yield and lower price fluctuations than is the case with more traditional fixed-income securities of comparable rating and maturity. In addition, when prepayments of principal are made on the underlying mortgages during periods of rising interest rates, the Fund may potentially reinvest the proceeds of such prepayments at rates higher than those at which they were previously invested. Mortgages underlying most ARMs, however, have limits on the allowable annual or lifetime increases that can be made in the interest rate that the mortgagor pays. Therefore, if current interest rates rise above such limits over the period of the limitation, the Fund, when holding an ARM, does not benefit from further increases in interest rates. Moreover, when interest rates are in excess of the coupon rates (i.e., the rates being paid by mortgagors) of the mortgages, ARMs behave more like fixed-income securities and less like adjustable-rate securities and are subject to the risks associated with fixed-income securities. In addition, during periods of rising interest rates, increases in the coupon rate of ARMs generally lag current market interest rates slightly, thereby creating the potential for capital depreciation on such securities. Sub-Prime Mortgages . Sub-prime mortgages are mortgages rated below “A” by Moody’s, S&P or Fitch. Historically, sub-prime mortgage loans have been made to borrowers with blemished (or non-existent) credit records, and the borrower is charged a higher interest rate to compensate for the greater risk of delinquency and the higher costs of loan servicing and collection. Sub-prime mortgages are subject to both state and federal anti-predatory lending statutes that carry potential liability to secondary market purchasers such as the Fund. Sub-prime mortgages have certain characteristics and associated risks similar to below investment grade securities, including a higher degree of credit risk, and certain characteristics and associated risks similar to MBS, including prepayment risk. Mortgage REITs . A real estate investment trust (“REIT”) is a corporation, or a business trust that would otherwise be taxed as a corporation, that meets the definitional requirements applicable to REITs under the Internal Revenue Code of 1986, as amended (the “Code”). The Code permits a qualifying REIT to deduct dividends paid, thereby generally eliminating corporate level U.S. federal income tax and effectively making the REIT a pass-through vehicle for U.S. federal income tax purposes. To meet the definitional requirements of the Code, a REIT must, among other things, invest substantially all of its assets in interests in real estate (including mortgages and other REITs) or cash and government securities, derive most of its income from rents from real property or interest on loans secured by mortgages on real property, and distribute to shareholders annually substantially all of its otherwise taxable income. Mortgage REITs invest mostly in mortgages on real estate, which may secure construction, development or long-term loans, and the main source of their income is mortgage interest payments. The value of securities issued by REITs is affected by tax and regulatory requirements and by perceptions of management skill. They also are subject to heavy cash flow dependency and the possibility of failing to qualify for REIT status under the Code or to maintain exemption from the Investment Company Act. Mortgage Related Derivative Instruments . The Fund may invest in MBS credit default swaps. MBS credit default swaps include swaps the reference obligation for which is an MBS or related index, such as the CMBX Index (a tradeable index referencing a basket of CMBS), the TRX Index (a tradeable index referencing total return swaps based on CMBS) or the ABX Index (a tradeable index referencing a basket of sub-prime MBS). The Fund may engage in other derivative transactions related to MBS, including purchasing and selling exchange-listed and over-the-counter put and call options, futures and forwards on mortgages and MBS. The Fund may invest in newly developed mortgage related derivatives that may hereafter become available. Other Mortgage Related Securities . Other mortgage related securities include securities other than those described above that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property. Other mortgage related securities may be equity or debt securities issued by agencies or instrumentalities of the U.S. Government or by private originators of, or investors in, mortgage loans, including savings and loan associations, homebuilders, mortgage banks, commercial banks, investment banks, partnerships, trusts and special purpose entities of the foregoing. Asset-Backed Securities. Asset-backed securities (“ABS”) are a form of structured debt obligation. The securitization techniques used for ABS are similar to those used for MBS. ABS are bonds backed by pools of loans or other receivables. The collateral for these securities may include home equity loans, automobile and credit card receivables, boat loans, computer leases, airplane leases, mobile home loans, recreational vehicle loans and hospital account receivables. The Fund may invest in these and other types of ABS that may be developed in the future. ABS present certain risks that are not presented by mortgage related securities. Primarily, these securities may provide the Fund with a less effective security interest in the related collateral than do mortgage related securities. Therefore, there is the possibility that recoveries on the underlying collateral may not, in some cases, be available to support payments on these securities. Collateralized Loan Obligations. A Collateralized Loan Obligation (“CLO”) is a structured debt security, issued by a financing company (generally called a special purpose vehicle or “SPV”), that was created to reapportion the risk and return characteristics of a pool of bank loans. Investors in CLOs bear the credit risk of the underlying collateral. The bank loans are used as collateral supporting the various debt tranches issued by the SPV. Multiple tranches of securities are issued by the CLO, offering investors various maturity and credit risk characteristics. Tranches are categorized as senior, mezzanine, or subordinated/equity, according to their degree of risk. The key feature of the CLO structure is the prioritization of the cash flows from a pool of debt securities among the several classes of the CLO. If there are defaults or the CLO’s collateral otherwise underperforms, scheduled payments to senior tranches take precedence over those of mezzanine tranches, and scheduled payments to mezzanine tranches take precedence over those to subordinated/equity tranches. The Fund may invest in the equity or residual portion of the capital structure of CLOs. The SPV is a company founded solely for the purpose of securitizing payment claims. On this basis, marketable securities are issued which, due to the diversification of the underlying risk, generally represent a lower level of risk than the original assets. The redemption of the securities issued by the SPV takes place at maturity out of the cash flow generated by the collected claims. The vast majority of CLOs are actively managed by an independent investment manager. U.S. Government Debt Securities. The Fund may invest in debt securities issued or guaranteed by the U.S. Government, its agencies or instrumentalities, including U.S. Treasury obligations, which differ in their interest rates, maturities and times of issuance. Such obligations include U.S. Treasury bills (maturity of one year or less), U.S. Treasury notes (maturity of one to ten years) and U.S. Treasury bonds (generally maturities of greater than ten years), including the principal components or the interest components issued by the U.S. Government under the separate trading of registered interest and principal securities program (i.e., “STRIPS”), all of which are backed by the full faith and credit of the United States. Restricted and Illiquid Investments. The Fund may invest without limitation in illiquid or less liquid investments or investments in which no secondary market is readily available or which are otherwise illiquid, including private placement securities. Liquidity of an investment relates to the ability to dispose easily of the investment and the price to be obtained upon disposition of the investment, which may be less than would be obtained for a comparable more liquid investment. “Illiquid investments” are investments which cannot be sold within seven days in the ordinary course of business at approximately the value used by the Fund in determining its NAV. Illiquid investments may trade at a discount from comparable, more liquid investments. Illiquid investments are subject to legal or contractual restrictions on disposition or lack an established secondary trading market. Investment of the Fund’s assets in illiquid investments may restrict the ability of the Fund to dispose of its investments in a timely fashion and for a fair price as well as its ability to take advantage of market opportunities. Strategic Transactions and Other Management Techniques. In addition to the MBS derivatives discussed herein, the Fund may use a variety of other investment management techniques and instruments. The Fund may purchase and sell futures contracts, enter into various interest rate transactions and may purchase and sell (or write) exchange-listed and over-the-counter put and call options on securities and futures contracts (collectively, “Strategic Transactions”). Strategic Transactions may be used to attempt to protect against possible changes in the market value of the Fund’s portfolio resulting from trends in the debt securities markets, to protect the Fund’s unrealized gains in the value of its portfolio securities, to facilitate the sale of such securities for investment purposes, to manage the dollar-weighted average life of the Fund’s portfolio or to establish a position in the securities markets as a temporary substitute for purchasing particular securities. There is no particular strategy that requires use of one technique rather than another as the decision to use any particular strategy or instrument is a function of market conditions and the composition of the portfolio. The use of Strategic Transactions to enhance current income may be speculative. The ability of the Fund to use Strategic Transactions successfully will depend on the Advisors’ ability to predict pertinent market movements as well as sufficient correlation among the instruments, which cannot be assured. The use of Strategic Transactions may result in losses greater than if they had not been used, may require the Fund to sell or purchase portfolio securities at inopportune times or for prices other than current market values, may limit the amount of appreciation the Fund can realize on an investment or may cause the Fund to hold a security that it might otherwise sell. Certain provisions of the Code may restrict or affect the ability of the Fund to engage in Strategic Transactions. In addition, the use of certain Strategic Transactions may give rise to taxable income and have certain other consequences. Interest Rate Transactions. The Fund may enter into interest rate swaps and purchase or sell interest rate caps and floors. The Fund expects to enter into these transactions primarily to preserve a return or spread on a particular investment or portion of its portfolio, as a duration management technique, to protect against any increase in the price of securities the Fund anticipates purchasing at a later date and/or to hedge against increases in the Fund’s costs associated with any leverage strategy. The Fund will ordinarily use these transactions as a hedge or for duration and risk management although it is permitted to enter into them to enhance income or gain. The Fund will not sell interest rate caps or floors that it does not own. Interest rate swaps involve the exchange by the Fund with another party of their respective commitments to pay or receive interest (e.g., an exchange of floating rate payments for fixed rate payments with respect to a notional amount of principal). The purchase of an interest rate cap entitles the purchaser, to the extent that the level of a specified interest rate exceeds a predetermined interest rate (i.e., the strike price), to receive payments of interest on a notional principal amount from the party selling such interest rate cap. The purchase of an interest rate floor entitles the purchaser, to the extent that the level of a specified interest rate falls below a predetermined interest rate (i.e., the strike price), to receive payments of interest on a notional principal amount from the party selling such interest rate floor. For example, if the Fund holds a debt instrument with an interest rate that is reset only once each year, it may swap the right to receive interest at this fixed rate for the right to receive interest at a rate that is reset every week. This would enable the Fund to offset a decline in the value of the debt instrument due to rising interest rates but would also limit its ability to benefit from falling interest rates. Conversely, if the Fund holds a debt instrument with an interest rate that is reset every week and it would like to lock in what it believes to be a high interest rate for one year, it may swap the right to receive interest at this variable weekly rate for the right to receive interest at a rate that is fixed for one year. Such a swap would protect the Fund from a reduction in yield due to falling interest rates and may permit the Fund to enhance its income through the positive differential between one week and one year interest rates, but would preclude it from taking full advantage of rising interest rates. The Fund may hedge both its assets and liabilities through interest rate swaps, caps and floors. Usually, payments with respect to interest rate swaps will be made on a net basis (i.e., the two payment streams are netted out) with the Fund receiving or paying, as the case may be, only the net amount of the two payments on the payment dates. If there is a default by the other party to an uncleared interest rate swap transaction, generally the Fund will have contractual remedies pursuant to the agreements related to the transaction. With respect to interest rate swap transactions cleared through a central clearing counterparty, a clearing organization will be substituted for the counterparty and will guaranty the parties’ performance under the swap agreement. However, there can be no assurance that the clearing organization will satisfy its obligation to the Fund or that the Fund would be able to recover the full amount of assets deposited on its behalf with the clearing organization in the event of the default by the clearing organization or the Fund’s clearing broker. Certain U.S. federal income tax requirements may limit the Fund’s ability to engage in interest rate swaps. Distributions attributable to transactions in interest rate swaps generally will be taxable as ordinary income to shareholders. Repurchase Agreements. The Fund may enter into repurchase agreements. A repurchase agreement is a contractual agreement whereby the seller of securities agrees to repurchase the same security at a specified price on a future date agreed upon by the parties. The agreed upon repurchase price determines the yield during the Fund’s holding period. Repurchase agreements are considered to be loans collateralized by the underlying security that is the subject of the repurchase contract. Income generated from transactions in repurchase agreements will be taxable. The Fund will only enter into repurchase agreements with registered securities dealers or domestic banks that, in the opinion of the Advisors, present minimal credit risk. The risk to the Fund is limited to the ability of the issuer to pay the agreed upon repurchase price on the delivery date; however, although the value of the underlying collateral at the time the transaction is entered into always equals or exceeds the agreed upon repurchase price, if the value of the collateral declines there is a risk of loss of both principal and interest. In the event of default, the collateral may be sold but the Fund might incur a loss if the value of the collateral declines, and might incur disposition costs or experience delays in connection with liquidating the collateral. In addition, if bankruptcy proceedings are commenced with respect to the seller of the security, realization upon the collateral by the Fund may be delayed or limited. The Advisors will monitor the value of the collateral at the time the transaction is entered into and at all times subsequent during the term of the repurchase agreement in an effort to determine that such value always equals or exceeds the agreed upon repurchase price. In the event the value of the collateral declines below the repurchase price, the Advisors will demand additional collateral from the issuer to increase the value of the collateral to at least that of the repurchase price, including interest. Reverse Repurchase Agreements. The Fund may enter into reverse repurchase agreements with respect to its portfolio investments subject to the investment restrictions set forth herein. Reverse repurchase agreements involve the sale of securities held by the Fund with an agreement by the Fund to repurchase the securities at an agreed upon price, date and interest payment. In accordance with Rule 18f-4 under the Investment Company Act, when the Fund engages in reverse repurchase agreements and similar financing transactions, the Fund may either (i) maintain asset coverage of at least 300% with respect to such transactions and any other borrowings in the aggregate, or (ii) treat such transactions as “derivatives transactions” and comply with Rule 18f-4 with respect to such transactions. See “Additional Risk Factors—Risk Factors in Strategic Transactions and Derivatives—Rule 18f-4 Under the Investment Company Act” in the SAI. Reverse repurchase agreements involve the risk that the market value of the securities acquired in connection with the reverse repurchase agreement may decline below the price of the securities the Fund has sold but is obligated to repurchase. Also, reverse repurchase agreements involve the risk that the market value of the securities retained in lieu of sale by the Fund in connection with the reverse repurchase agreement may decline in price. If the buyer of securities under a reverse repurchase agreement files for bankruptcy or becomes insolvent, such buyer or its trustee or receiver may receive an extension of time to determine whether to enforce the Fund’s obligation to repurchase the securities and the Fund’s use of the proceeds of the reverse repurchase agreement may effectively be restricted pending such decision. Also, the Fund would bear the risk of loss to the extent that the proceeds of the reverse repurchase agreement are less than the value of the securities subject to such agreement. The Fund also may effect simultaneous purchase and sale transactions that are known as “sale-buybacks.” A sale-buyback is similar to a reverse repurchase agreement, except that in a sale-buyback, the counterparty that purchases the security is entitled to receive any principal or interest payments made on the underlying security pending settlement of the Fund’s repurchase of the underlying security. Dollar Rolls. The Fund may enter into “dollar roll” transactions. In a dollar roll transaction, the Fund sells a mortgage related or other security to a dealer and simultaneously agrees to repurchase a similar security (but not the same security) in the future at a pre-determined price. A dollar roll transaction can be viewed, like a reverse repurchase agreement, as a collateralized borrowing in which the Fund pledges a mortgage related security to a dealer to obtain cash. However, unlike reverse repurchase agreements, the dealer with which the Fund enters into a dollar roll transaction is not obligated to return the same securities as those originally sold by the Fund, but rather only securities which are “substantially identical,” which generally means that the securities repurchased will bear the same interest rate and a similar maturity as those sold, but the pools of mortgages collateralizing those securities may have different prepayment histories than those sold. During the period between the sale and repurchase, the Fund will not be entitled to receive interest and principal payments on the securities sold. Proceeds of the sale will be invested in additional instruments for the Fund and the income from these investments will generate income for the Fund. If such income does not exceed the income, capital appreciation and gain that would have been realized on the securities sold as part of the dollar roll, the use of this technique will diminish the investment performance of the Fund compared with what the performance would have been without the use of dollar rolls. Rule 18f-4 under the Investment Company Act permits the Fund to enter into when-issued or forward-settling securities (e.g., dollar rolls and firm and standby commitments, including to-be-announced (“TBA”) commitments) and non-standard settlement cycle securities notwithstanding the limitation on the issuance of senior securities in Section 18 of the Investment Company Act, provided that the transaction meets the Delayed-Settlement Securities Provision (as defined below under “The Fund’s Investments—Portfolio Contents and Techniques—When-Issued Securities, Delayed Delivery Securities and Forward Commitment Securities”). If a when-issued, forward-settling or non-standard settlement cycle security does not satisfy the Delayed-Settlement Securities Provision, then it is treated as a derivatives transaction under Rule 18f-4. See “Additional Risk Factors—Risk Factors in Strategic Transactions and Derivatives—Rule 18f-4 Under the Investment Company Act” in the SAI. Dollar roll transactions involve the risk that the market value of the securities the Fund is required to purchase may decline below the agreed upon repurchase price of those securities. The Fund’s right to purchase or repurchase securities may be restricted. Successful use of mortgage dollar rolls may depend upon the investment manager’s ability to correctly predict interest rates and prepayments. There is no assurance that dollar rolls can be successfully employed. Other Investment Companies. The Fund may invest in securities of other investment companies (including exchange-traded funds (“ETFs”), business development companies and money market funds, including other investment companies managed by the Advisor or its affiliates), subject to applicable regulatory limits, that invest primarily in securities of the types in which the Fund may invest directly. The Fund generally expects to invest in other investment companies either during periods when it has large amounts of uninvested cash, such as the period shortly after the Fund receives the proceeds of the offering of its common shares (or preferred shares, should the Fund determine to issue preferred shares in the future), or during periods when there is a shortage of attractive fixed income securities available in the market. As a shareholder in an investment company, the Fund will bear its ratable share of that investment company’s expenses and will remain subject to payment of the Fund’s advisory and other fees and expenses with respect to assets so invested. Holders of common shares will therefore be subject to duplicative expenses to the extent the Fund invests in other investment companies (except that it will not be subject to duplicate advisory fees with respect to other investment companies managed by the Advisor or its affiliates). The Advisors will take expenses into account when evaluating the investment merits of an investment in an investment company relative to available equity and/or fixed-income securities investments. In addition, the securities of other investment companies may be leveraged and will therefore be subject to the same leverage risks to which the Fund may be subject to the extent it employs a leverage strategy. As described in the sections entitled “Risks” and “Leverage,” the NAV and market value of leveraged shares will be more volatile and the yield to shareholders will tend to fluctuate more than the yield generated by unleveraged shares. Investment companies may have investment policies that differ from those of the Fund. In addition, to the extent the Fund invests in other investment companies that are not managed by the Advisor or its affiliates, the Fund will be dependent upon the investment and research abilities of persons other than the Advisor. The Fund may invest in ETFs, which are investment companies that typically aim to track or replicate a desired index, such as a sector, market or global segment. ETFs are typically passively managed and their shares are traded on a national exchange or The NASDAQ Stock Market, Inc. ETFs do not sell individual shares directly to investors and only issue their shares in large blocks known as “creation units.” The investor purchasing a creation unit may sell the individual shares on a secondary market. Therefore, the liquidity of ETFs depends on the adequacy of the secondary market. There can be no assurance that an ETF’s investment objective will be achieved, as ETFs based on an index may not replicate and maintain exactly the composition and relative weightings of securities in the index. ETFs are subject to the risks of investing in the underlying securities. The Fund, as a holder of the securities of the ETF, will bear its pro rata portion of the ETF’s expenses, including advisory fees (except that it will not be subject to duplicate advisory fees with respect to ETFs managed by the Advisor or its affiliates). These expenses are in addition to the direct expenses of the Fund’s own operations. The Fund treats its investments in other investment companies that invest substantially all of their assets in fixed income securities as investments in fixed income securities. Short-Term Debt Securities; Temporary Defensive Positions; Invest-Up Period. During temporary defensive periods (e.g., times when, in the Advisors’ opinion, temporary imbalances of supply and demand or other temporary dislocations in the market adversely affect the price at which fixed income securities are available, or in connection with the termination of the Fund) and in order to keep cash on hand fully invested, including the period during which the net proceeds of this offering of common shares (or preferred shares, should the Fund determine to issue preferred shares in the future) are being invested, the Fund may invest any percentage of its assets in liquid, short-term investments including high quality, short-term securities and securities of other open- or closed-end investment companies that invest primarily in securities of the type in which the Fund may invest directly. See “Investment Policies and Techniques—Cash Equivalents and Short-Term Debt Securities” in the SAI. The Advisors’ determination that they are temporarily unable to follow the Fund’s investment strategy or that it is impractical to do so will generally occur only in situations in which a market disruption event has occurred and where trading in the securities selected through application of the Fund’s investment strategy is extremely limited or absent or in connection with the termination of the Fund. Securities Lending. The Fund may lend portfolio securities to certain borrowers determined to be creditworthy by the Advisor, including to borrowers affiliated with the Advisor. The borrowers provide collateral that is maintained in an amount at least equal to the current market value of the securities loaned. No securities loan will be made on behalf of the Fund if, as a result, the aggregate value of all securities loans of the Fund exceeds one-third of the value of the Fund’s total assets (including the value of the collateral received). The Fund may terminate a loan at any time and obtain the return of the securities loaned. The Fund receives the value of any interest or cash or non-cash distributions paid on the loaned securities. With respect to loans that are collateralized by cash, the borrower may be entitled to receive a fee based on the amount of cash collateral. The Fund is compensated by the difference between the amount earned on the reinvestment of cash collateral and the fee paid to the borrower. In the case of collateral other than cash, the Fund is compensated by a fee paid by the borrower equal to a percentage of the market value of the loaned securities. Any cash collateral received by the Fund for such loans, and uninvested cash, may be invested, among other things, in a private investment company managed by an affiliate of the Advisor or in registered money market funds advised by the Advisor or their affiliates; such investments are subject to investment risk. The Fund conducts its securities lending pursuant to an exemptive order from the SEC permitting it to lend portfolio securities to borrowers affiliated with the Fund and to retain an affiliate of the Fund as lending agent. To the extent that the Fund engages in securities lending, BlackRock Investment Management, LLC (“BIM”), an affiliate of the Advisor, acts as securities lending agent for the Fund, subject to the overall supervision of the Advisor. BIM administers the lending program in accordance with guidelines approved by the Board. To the extent the Fund engages in securities lending, the Fund retains a portion of securities lending income and remits a remaining portion to BIM as compensation for its services as securities lending agent. Securities lending income is equal to the total of income earned from the reinvestment of cash collateral (and excludes collateral investment expenses as defined below), and any fees or other payments to and from borrowers of securities. As securities lending agent, BIM bears all operational costs directly related to securities lending. The Fund is responsible for expenses in connection with the investment of cash collateral received for securities on loan (the “collateral investment expenses”). The cash collateral is invested in a private investment company managed by the Advisor or its affiliates. However, BIM has agreed to cap the collateral investment expenses of the private investment company to an annual rate of 0.04%. In addition, in accordance with the exemptive order, the investment adviser to the private investment company will not charge any advisory fees with respect to shares purchased by the Fund. Such shares also will not be subject to a sales load, distribution fee or service fee. If the private investment company’s weekly liquid assets fall below 30% of its total assets, BIM, as managing member of the private investment company, is permitted at any time, if it determines it to be in the best interests of the private investment company, to impose a liquidity fee of up to 2% of the value of units withdrawn or impose a redemption gate that temporarily suspends the right of withdrawal out of the private investment company. In addition, if the private investment company’s weekly liquid assets fall below 10% of its total assets at the end of any business day, the private investment company will impose a liquidity fee in the default amount of 1% of the amount withdrawn, generally effective as of the next business day, unless BIM determines that a higher (not to exceed 2%) or lower fee level or not imposing a liquidity fee is in the best interests of the private investment company. The shares of the private investment company purchased by the Fund would be subject to any such liquidity fee or redemption gate imposed. Under the securities lending program, the Fund is categorized into a specific asset class. The determination of the Fund’s asset class category (fixed income, domestic equity, international equity, or fund of funds), each of which may be subject to a different fee arrangement, is based on a methodology agreed to between the Fund and BIM. Pursuant to the current securities lending agreement: (i) if the Fund were to engage in securities lending, the Fund retains 82% of securities lending income (which excludes collateral investment expenses), and (ii) this amount can never be less than 70% of the sum of securities lending income plus collateral investment expenses. In addition, commencing the business day following the date that the aggregate securities lending income earned across the BlackRock Fixed-Income Complex in a calendar year exceeds a specified threshold, the Fund, pursuant to the current securities lending agreement, will receive for the remainder of that calendar year securities lending income as follows: (i) if the Fund were to engage in securities lending, 85% of securities lending income (which excludes collateral investment expenses); and (ii) this amount can never be less than 70% of the sum of securities lending income plus collateral investment expenses. Short Sales. The Fund may make short sales of securities. A short sale is a transaction in which the Fund sells a security it does not own in anticipation that the market price of that security will decline. The Fund may make short sales to hedge positions, for duration and risk management, in order to maintain portfolio flexibility or to enhance income or gain. When the Fund makes a short sale, it must borrow the security sold short and deliver it to the broker-dealer through which it made the short sale as collateral for its obligation to deliver the security upon conclusion of the sale. The Fund may have to pay a fee to borrow particular securities and is often obligated to pay over any payments received on such borrowed securities. The Fund’s obligation to replace the borrowed security will be secured by collateral deposited with the broker-dealer, usually cash, U.S. Government securities or other liquid securities. Depending on arrangements made with the broker-dealer from which it borrowed the security regarding payment over of any payments received by the Fund on such security, the Fund may not receive any payments (including interest) on its collateral deposited with such broker-dealer. If the price of the security sold short increases between the time of the short sale and the time the Fund replaces the borrowed security, the Fund will incur a loss; conversely, if the price declines, the Fund will realize a gain. Any gain will be decreased, and any loss increased, by the transaction costs described above. Although the Fund’s gain is limited to the price at which it sold the security short, its potential loss is theoretically unlimited. The Fund will not make a short sale if, after giving effect to such sale, the market value of all securities sold short exceeds 25% of the value of its Managed Assets or the Fund’s aggregate short sales of a particular class of securities exceeds 25% of the outstanding securities of that class. The Fund may also make short sales “against the box” without respect to such limitations. In this type of short sale, at the time of the sale, the Fund owns or has the immediate and unconditional right to acquire at no additional cost the identical security. The Fund must comply with Rule 18f-4 under the Investment Company Act with respect to its short sale borrowings, which are considered derivatives transactions under the Rule. See “Additional Risk Factors—Risk Factors in Strategic Transactions and Derivatives—Rule 18f-4 Under the Investment Company Act” in the SAI. When-Issued, Delayed Delivery Securities and Forward Commitment Securities. The Fund may purchase securities on a “when-issued” basis and may purchase or sell securities on a “forward commitment” basis (including on a “TBA” (to be announced) basis) or on a “delayed delivery” basis. When such transactions are negotiated, the price, which is generally expressed in yield terms, is fixed at the time the commitment is made, but delivery and payment for the securities take place at a later date. When-issued securities and forward commitments may be sold prior to the settlement date. If the Fund disposes of the right to acquire a when-issued security prior to its acquisition or disposes of its right to deliver or receive against a forward commitment, it might incur a gain or loss. Pursuant to recommendations of the Treasury Market Practices Group, which is sponsored by the Federal Reserve Board of New York, the Fund or its counterparty generally is required to post collateral when entering into certain forward-settling transactions, including without limitation TBA transactions. There is always a risk that the securities may not be delivered and that the Fund may incur a loss. A default by a counterparty may result in the Fund missing the opportunity of obtaining a price considered to be advantageous. The value of securities in these transactions on the delivery date may be more or less than the Fund’s purchase price. The Fund may bear the risk of a decline in the value of the security in these transactions and may not benefit from an appreciation in the value of the security during the commitment period. Settlements in the ordinary course are not treated by the Fund as when-issued or forward commitment transactions and accordingly are not subject to the foregoing restrictions. The market value of the securities underlying a commitment to purchase securities, and any subsequent fluctuations in their market value, is taken into account when determining the NAV of the Fund starting on the day the Fund agrees to purchase the securities. The Fund does not earn interest on the securities it has committed to purchase until they are paid for and delivered on the settlement date. Rule 18f-4 under the Investment Company Act permits the Fund to enter into when-issued or forward-settling securities (e.g., firm and standby commitments, including TBA commitments, and dollar rolls) and non-standard settlement cycle securities notwithstanding the limitation on the issuance of senior securities in Section 18 of the Investment Company Act, provided that the Fund intends to physically settle the transaction and the transaction will settle within 35 days of its trade date (the “Delayed-Settlement Securities Provision”). If a when-issued, forward-settling or non-standard settlement cycle security does not satisfy the Delayed-Settlement Securities Provision, then it is treated as a derivatives transaction under Rule 18f-4. See “Additional Risk Factors—Risk Factors in Strategic Transactions and Derivatives—Rule 18f-4 Under the Investment Company Act” in the SAI. |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  | RISKS The NAV and market price of, and dividends paid on, the common shares will fluctuate with and be affected by, among other things, the risks of investing in the Fund. General Risks Please refer to the section of the Fund’s most recent annual report on Form N-CSR entitled “Investment Objectives, Policies and Risks—Risk Factors” , which is incorporated by reference herein, for a discussion of the general risks of investing in the Fund. Other Risks When-Issued, Forward Commitment and Delayed Delivery Transactions Risk The Fund may purchase securities on a when-issued basis (including on a forward commitment or “TBA” (to be announced) basis) and may purchase or sell securities for delayed delivery. When-issued and delayed delivery transactions occur when securities are purchased or sold by the Fund with payment and delivery taking place in the future to secure an advantageous yield or price. Securities purchased on a when-issued or delayed delivery basis may expose the Fund to counterparty risk of default as well as the risk that securities may experience fluctuations in value prior to their actual delivery. The Fund will not accrue income with respect to a when-issued or delayed delivery security prior to its stated delivery date. Purchasing securities on a when-issued or delayed delivery basis can involve the additional risk that the price or yield available in the market when the delivery takes place may not be as favorable as that obtained in the transaction itself. Collateralized Debt Obligations Risk In addition to the typical risks associated with fixed-income securities and asset-backed securities, collateralized debt obligations (“CDOs”), including collateralized loan obligations (“CLOs”), carry additional risks including, but not limited to: (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments; (ii) the risk that the collateral may default or decline in value or be downgraded, if rated by a nationally recognized statistical rating organization; (iii) the Fund may invest in tranches of CDOs that are subordinate to other tranches; (iv) the structure and complexity of the transaction and the legal documents could lead to disputes among investors regarding the characterization of proceeds; (v) the investment return achieved by the Fund could be significantly different than those predicted by financial models; (vi) the lack of a readily available secondary market for CDOs; (vii) the risk of forced “fire sale” liquidation due to technical defaults such as coverage test failures; and (viii) the CDO’s manager may perform poorly. Dollar Roll Transactions Risk Dollar roll transactions involve the risk that the market value of the securities the Fund is required to purchase may decline below the agreed upon repurchase price of those securities. If the broker/dealer to which the Fund sells securities becomes insolvent, the Fund’s right to purchase or repurchase securities may be restricted. Successful use of dollar rolls may depend upon the Advisor’s ability to predict correctly interest rates and prepayments. There is no assurance that dollar rolls can be successfully employed. These transactions may involve leverage. Short Sales Risk Short-selling involves selling securities which may or may not be owned and borrowing the same securities for delivery to the purchaser, with an obligation to replace the borrowed securities at a later date. If the price of the security sold short increases between the time of the short sale and the time the Fund replaces the borrowed security, the Fund will incur a loss; conversely, if the price declines, the Fund will realize a capital gain. Any gain will be decreased, and any loss will be increased, by the transaction costs incurred by the Fund, including the costs associated with providing collateral to the broker-dealer (usually cash and liquid securities) and the maintenance of collateral with its custodian. Although the Fund’s gain is limited to the price at which it sold the security short, its potential loss is theoretically unlimited. Short-selling necessarily involves certain additional risks. However, if the short seller does not own the securities sold short (an uncovered short sale), the borrowed securities must be replaced by securities purchased at market prices in order to close out the short position, and any appreciation in the price of the borrowed securities would result in a loss. Uncovered short sales expose the Fund to the risk of uncapped losses until a position can be closed out due to the lack of an upper limit on the price to which a security may rise. Purchasing securities to close out the short position can itself cause the price of the securities to rise further, thereby exacerbating the loss. There is the risk that the securities borrowed by the Fund in connection with a short-sale must be returned to the securities lender on short notice. If a request for return of borrowed securities occurs at a time when other short-sellers of the security are receiving similar requests, a “short squeeze” can occur, and the Fund may be compelled to replace borrowed securities previously sold short with purchases on the open market at the most disadvantageous time, possibly at prices significantly in excess of the proceeds received at the time the securities were originally sold short. Investment Companies and ETFs Risk Subject to the limitations set forth in the Investment Company Act and the rules thereunder, the Fund may acquire shares in other investment companies and in ETFs and business development companies (“BDCs”), some of which may be affiliated investment companies. The market value of the shares of other investment companies and ETFs may differ from their NAV. As an investor in investment companies, including ETFs and BDCs, the Fund would bear its ratable share of that entity’s expenses, including its investment advisory and administration fees, while continuing to pay its own advisory and administration fees and other expenses (to the extent not offset by the Advisor through waivers). As a result, shareholders will be absorbing duplicate levels of fees with respect to investments in other investment companies, including ETFs and BDCs (to the extent not offset by the Advisor through waivers). The securities of other investment companies, including ETFs and BDCs, in which the Fund may invest may be leveraged. As a result, the Fund may be indirectly exposed to leverage through an investment in such securities. An investment in securities of other investment companies, including ETFs and BDCs, that use leverage may expose the Fund to higher volatility in the market value of such securities and the possibility that the Fund’s long-term returns on such securities (and, indirectly, the long-term returns of shares of the Fund) will be diminished. The portfolios of ETFs are generally not actively managed and may be affected by a general decline in market segments relating to its index. An ETF typically invests in securities included in, or representative of, its index regardless of their investment merits and does not attempt to take defensive positions in declining markets. Securities Lending Risk Securities lending involves exposure to certain risks, including operational risk (i.e., the risk of losses resulting from problems in the settlement and accounting process), “gap” risk (i.e., the risk of a mismatch between the return on cash collateral reinvestments and the fees the Fund has agreed to pay a borrower), foreign exchange risk (i.e., the risk of a shortfall at default when a cash collateral investment is denominated in a currency other than the currency of the assets being loaned due to movements in foreign exchange rates), and credit, legal, counterparty and market risks (including the risk that market events, including but not limited to corporate actions, could lead the Fund to lend securities that are trading at a premium due to increased demand, or to recall loaned securities or to lend less or not at all, which could lead to reduced securities lending revenue). If the Fund were to lend out securities that are subject to a corporate action and commit to the borrower a particular election as determined by the Advisor, the benefit the Fund would receive in respect of committing to such election may or may not be less than the benefit the Fund would have received from making a different election in such corporate action. If a securities lending counterparty were to default, the Fund would be subject to the risk of a possible delay in receiving collateral or in recovering the loaned securities, or to a possible loss of rights in the collateral. In the event a borrower does not return the Fund’s securities as agreed, the Fund’s ability to participate in a corporate action event may be impacted, or the Fund may experience losses if the proceeds received from liquidating the collateral do not at least equal the value of the loaned security at the time the collateral is liquidated, plus the transaction costs incurred in purchasing replacement securities. This latter event could trigger adverse tax consequences for the Fund. The Fund could lose money if its short-term investment of the collateral declines in value over the period of the loan. Substitute payments received by the Fund representing dividends paid on securities loaned out by the Fund will not be considered qualified dividend income, and distributions by the Fund of such substitute payments will not constitute qualified dividend income. Additionally, substitute payments received by the Fund representing qualified REIT dividends paid on REIT securities loaned out by the Fund will not be considered qualified REIT dividends, and distributions by the Fund of such substitute payments will not be eligible for a 20% deduction currently available for ordinary REIT dividends paid to non-corporate shareholders provided certain other requirements are satisfied. The securities lending agent will take into account the tax effects on shareholders caused by these differences in connection with the Fund’s securities lending program. Substitute payments received on tax-exempt securities loaned out will not be tax-exempt income. There could also be changes in the status of issuers under applicable laws and regulations, including tax regulations, that may impact the regulatory or tax treatment of loaned securities and could, for example, result in a delay in the payment of dividend equivalent payments owed to the Fund (as permitted by applicable law). Regulations adopted by global prudential regulators require certain bank-regulated counterparties and certain of their affiliates to include in certain financial contracts, including many securities lending agreements, terms that delay or restrict the rights of counterparties, such as the Fund, to terminate such agreements, foreclose upon collateral, exercise other default rights or restrict transfers of credit support in the event that the counterparty and/or its affiliates are subject to certain types of resolution or insolvency proceedings. It is possible that these requirements, as well as potential additional government regulation and other developments in the market, could adversely affect the Fund’s ability to terminate existing securities lending agreements or to realize amounts to be received under such agreements. Prudential regulation may also favor lenders that can provide additional protections, such as liens that are exercisable upon lender default, to bank borrowers. The Fund may provide additional protections to bank borrowers, where permitted pursuant to the Fund’s investment policies and if the Advisor believes doing so is in the best interest of the Fund. Swaps Risk Swaps are a type of derivative. Swap agreements involve the risk that the party with which the Fund has entered into the swap will default on its obligation to pay the Fund and the risk that the Fund will not be able to meet its obligations to pay the other party to the agreement. In order to seek to hedge the value of the Fund’s portfolio, to hedge against increases in the Fund’s cost associated with interest payments on any outstanding borrowings or to seek to increase the Fund’s return, the Fund may enter into swaps, including interest rate swap, total return swap (sometimes referred to as a “contract for difference”) and/or credit default swap transactions. In interest rate swap transactions, there is a risk that yields will move in the direction opposite of the direction anticipated by the Fund, which would cause the Fund to make payments to its counterparty in the transaction that could adversely affect Fund performance. In addition to the risks applicable to swaps generally (including counterparty risk, high volatility, illiquidity risk and credit risk), credit default swap transactions involve special risks because they are difficult to value, are highly susceptible to liquidity and credit risk, and generally pay a return to the party that has paid the premium only in the event of an actual default by the issuer of the underlying obligation (as opposed to a credit downgrade or other indication of financial difficulty). The United States, the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the “Dodd-Frank Act”), requires that certain derivatives with U.S. persons must be executed on a regulated market and a substantial portion of OTC derivatives must be submitted for clearing to regulated clearinghouses. As a result, swap transactions entered into by the Fund may become subject to various requirements applicable to swaps under the Dodd-Frank Act, including clearing, exchange-execution, reporting and recordkeeping requirements, which may make it more difficult and costly for the Fund to enter into swap transactions and may also render certain strategies in which the Fund might otherwise engage impossible or so costly that they will no longer be economical to implement. Furthermore, the number of counterparties that may be willing to enter into swap transactions with the Fund may also be limited if the swap transactions with the Fund are subject to the swap regulation under the Dodd-Frank Act. Credit default and total return swap agreements may effectively add leverage to the Fund’s portfolio because, in addition to its Managed Assets, the Fund would be subject to investment exposure on the notional amount of the swap in excess of any premium and margin required to establish and maintain the position. Total return swap agreements are subject to market risk as well as the risk that a counterparty will default on its payment obligations to the Fund thereunder. The Fund is not required to enter into swap transactions for hedging purposes or to enhance income or gain and may choose not to do so. In addition, the swaps market is subject to a changing regulatory environment. It is possible that regulatory or other developments in the swaps market could adversely affect the Fund’s ability to successfully use swaps. Inflation Risk Inflation risk is the risk that the value of assets or income from investment will be worth less in the future, as inflation decreases the value of money. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy. As inflation increases, the real value of the common shares and distributions on those shares can decline. In addition, during any periods of rising inflation, interest rates on any borrowings by the Fund would likely increase, which would tend to further reduce returns to the holders of common shares. Deflation Risk Deflation risk is the risk that prices throughout the economy decline over time, which may have an adverse effect on the market valuation of companies, their assets and their revenues. In addition, deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of the Fund’s portfolio. Risk Associated with Recent Market Events Although interest rates were unusually low in recent years in the U.S. and abroad, in 2022, the Federal Reserve and certain foreign central banks raised interest rates as part of their efforts to address rising inflation. The Federal Reserve and certain foreign central banks have started to lower interest rates, though economic or other factors, such as inflation, could stop such changes. It is difficult to accurately predict the pace at which interest rates might change, the timing, frequency or magnitude of any such changes in interest rates, or when such changes might stop or again reverse course. Additionally, various economic and political factors could cause the Federal Reserve or other foreign central banks to change their approach in the future and such actions may result in an economic slowdown both in the U.S. and abroad. Unexpected changes in interest rates could lead to significant market volatility or reduce liquidity in certain sectors of the market. Deteriorating economic fundamentals may, in turn, increase the risk of default or insolvency of particular issuers, negatively impact market value, cause credit spreads to widen, and reduce bank balance sheets. Any of these could cause an increase in market volatility, reduce liquidity across various markets or decrease confidence in the markets, which could negatively affect the value of debt instruments held by the Fund and result in a negative impact on the Fund’s performance. See “—Inflation Risk.” Recent policy initiatives undertaken by the U.S. government have the potential to impact international relations, trade agreements and the overall regulatory environment in ways that could create uncertainty and instability in domestic and global markets, and could adversely affect the investment performance of the Fund. In particular, actions taken by the U.S. government in respect of international trade relations could lead to trade wars, increased costs for imported goods, disruptions in supply chains, reduced foreign investment, and instability in regions where the Fund invests. Political and diplomatic events within the United States, including a contentious domestic political environment, changes in political party control of one or more branches of the U.S. Government, the U.S. Government’s inability at times to agree on a long-term budget and deficit reduction plan, the threat of a U.S. Government shutdown, and disagreements over, or threats not to increase, the U.S. Government’s borrowing limit (or “debt ceiling”), as well as political and diplomatic events abroad, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. A downgrade of the ratings of U.S. Government debt obligations, or concerns about the U.S. Government’s credit quality in general, could have a substantial negative effect on the U.S. and global economies. For example, concerns about the U.S. Government’s credit quality may cause increased volatility in the stock and bond markets, higher interest rates, reduced prices and liquidity of U.S. Treasury securities, and/or increased costs of various kinds of debt. Moreover, although the U.S. Government has honored its credit obligations, there remains a possibility that the United States could default on its obligations. The consequences of such an unprecedented event are impossible to predict, but it is likely that a default by the United States would be highly disruptive to the U.S. and global securities markets and could significantly impair the value of the Fund’s investments. In recent years, some countries, including the United States, have adopted more protectionist trade policies. Slowing global economic growth, the rise in protectionist trade policies, inflationary pressures, changes to some major international trade agreements, risks associated with the trade agreements between countries and regions, including the U.S. and other foreign nations, political or economic dysfunction within some countries or regions, including the U.S., and dramatic changes in commodity and currency prices could affect the economies of many nations in ways that cannot necessarily be foreseen at the present time. In addition, if the U.S. dollar continues to be strong, it may decrease foreign demand for U.S. assets, which could have a negative impact on certain issuers and/or industries. Reference Rate Replacement Risk The Fund may be exposed to financial instruments that recently transitioned from, or continue to be tied to, the London Interbank Offered Rate (“LIBOR”) to determine payment obligations, financing terms, hedging strategies or investment value. The United Kingdom’s Financial Conduct Authority (“FCA”), which regulates LIBOR, has ceased publishing all LIBOR settings. In April 2023, however, the FCA announced that some USD LIBOR settings would continue to be published under a synthetic methodology until September 30, 2024 for certain legacy contracts. After September 30, 2024, the remaining synthetic LIBOR settings ceased to be published, and all LIBOR settings have permanently ceased. The Secured Overnight Financing Rate (“SOFR”) is a broad measure of the cost of borrowing cash overnight collateralized by U.S. Treasury securities in the repurchase agreement (“repo”) market and has been used increasingly on a voluntary basis in new instruments and transactions. Under U.S. regulations that implement a statutory fallback mechanism to replace LIBOR, benchmark rates based on SOFR have replaced LIBOR in certain financial contracts. Neither the effect of the LIBOR transition process nor its ultimate succ ess can yet be known. While some existing LIBOR-based instruments may contemplate a scenario where LIBOR is no longer available by providing for an alternative rate-setting methodology, there may be significant uncertainty regarding the effectiveness of any such alternative methodologies to replicate LIBOR. Not all existing LIBOR-based instruments may have alternative rate-setting provisions and there remains uncertainty regarding the willingness and ability of issuers to add alternative rate-setting provisions in certain existing instruments. Parties to contracts, securities or other instruments using LIBOR may disagree on transition rates or the application of transition regulation, potentially resulting in uncertainty of performance and the possibility of litigation. The Fund may have instruments linked to other interbank offered rates that may also cease to be published in the future. Market Disruption and Geopolitical Risk The occurrence of events similar to those in recent years, such as the aftermath of the war in Iraq, instability in Afghanistan, Pakistan, Egypt, Libya, Syria and the Middle East, international war or conflict (including the Israel-Hamas war), new and ongoing epidemics and pandemics of infectious diseases and other global health events, natural/environmental disasters, terrorist attacks in the United States and around the world, social and political discord, debt crises (such as the Greek crisis), sovereign debt downgrades, the Russian invasion of Ukraine, increasingly strained relations between the United States and a number of foreign countries, including historical adversaries, such as North Korea, Iran, China and Russia, and the international community generally, new and continued political unrest in various countries, such as Venezuela and Spain, the exit or potential exit of one or more countries from the EU or the EMU, and continued changes in the balance of political power among and within the branches of the U.S. Government, among others, may result in market volatility, may have long term effects on the U.S. and worldwide financial markets, and may cause further economic uncertainties in the United States and worldwide. Russia launched a large-scale invasion of Ukraine on February 24, 2022. The extent and duration of the military action, resulting sanctions and resulting future market disruptions, including declines in its stock markets and the value of the ruble against the U.S. dollar, in the region are impossible to predict, but could be significant. Any such disruptions caused by Russian military action or other actions (including cyberattacks and espionage) or resulting actual and threatened responses to such activity, including purchasing and financing restrictions, boycotts or changes in consumer or purchaser preferences, sanctions, tariffs or cyberattacks on the Russian government, Russian companies or Russian individuals, including politicians, could have a severe adverse effect on Russia and the European region, including significant negative impacts on the Russian economy, the European economy and the markets for certain securities and commodities, such as oil and natural gas, and may likely have collateral impacts on such sectors globally as well as other sectors. How long such military action and related events will last cannot be predicted. Trade tensions between the United States and China have led to concerns about economic stability and could have an adverse impact on global economic conditions. The United States and China have each been implementing increased tariffs on imports from the other, and the United States has also adopted certain targeted measures such as export controls or sanctions implicating Chinese companies and officials. While certain trade agreements have been agreed between the two countries, there remains much uncertainty as to whether the trade negotiations between the United States and China will be successful and how the trade war between the United States and China will progress. Uncertainty regarding the outcome of the trade tensions and the potential for a trade war could cause the U.S. dollar to decline against safe haven currencies, such as the Japanese yen and the Euro. Events such as these and their consequences are difficult to predict and it is unclear whether further tariffs may be imposed or other escalating actions may be taken in the future. If the trade war between the United States and China continues or escalates, or if additional tariffs or trade restrictions are implemented by the United States, China or other countries in connection with a global trade war, there could be material adverse effects on the global economy, and the Fund and its portfolio investments could be materially and adversely affected. On January 31, 2020, the United Kingdom officially left the European Union (Brexit), subject to a transitional period that ended December 31, 2020. The United Kingdom and European Union have reached an agreement on the terms of their future trading relationship effective January 1, 2021, which principally relates to the trading of goods rather than services, including financial services. Further discussions are to be held between the United Kingdom and the European Union in relation to matters not covered by the trade agreement, such as financial services. The Fund faces risks associated with the potential uncertainty and consequences that may follow Brexit, including with respect to volatility in exchange rates and interest rates. Brexit could adversely affect European or worldwide political, regulatory, economic or market conditions and could contribute to instability in global political institutions, regulatory agencies and financial markets. Brexit has also led to legal uncertainty and could lead to politically divergent national laws and regulations as a new relationship between the United Kingdom and European Union is defined and the United Kingdom determines which European Union laws to replace or replicate. Any of these effects of Brexit could adversely affect any of the companies to which the Fund has exposure and any other assets that the Fund invests in. The political, economic and legal consequences of Brexit are not yet known. In the short term, financial markets may experience heightened volatility, particularly those in the United Kingdom and Europe, but possibly worldwide. The United Kingdom and Europe may be less stable than they have been in recent years, and investments in the United Kingdom and the European Union may be difficult to value or subject to greater or more frequent volatility. In the longer term, there is likely to be a period of significant political, regulatory and commercial uncertainty as the United Kingdom continues to negotiate the terms of its future trading relationship with the European Union. Cybersecurity incidents affecting particular companies or industries may adversely affect the economies of particular countries, regions or parts of the world in which the Fund invests. The occurrence of any of these above events could have a significant adverse impact on the value and risk profile of the Fund’s portfolio. The Fund does not know how long the securities markets may be affected by similar events and cannot predict the effects of similar events in the future on the U.S. economy and securities markets. There can be no assurance that similar events and other market disruptions will not have other material and adverse implications. Regulation and Government Intervention Risk Federal, state, and other governments, their regulatory agencies or self-regulatory organizations may take actions that affect the regulation of the issuers in which the Fund invests in ways that are unforeseeable. Legislation or regulation may also change the way in which the Fund is regulated. Such legislation or regulation could limit or preclude the Fund’s ability to achieve its investment objective. In light of popular, political and judicial focus on finance related consumer protection, financial institution practices are also subject to greater scrutiny and criticism generally. In the case of transactions between financial institutions and the general public, there may be a greater tendency toward strict interpretation of terms and legal rights in favor of the consuming public, particularly where there is a real or perceived disparity in risk allocation and/or where consumers are perceived as not having had an opportunity to exercise informed consent to the transaction. In the event of conflicting interests between retail investors holding common shares of a closed-end investment company such as the Fund and a large financial institution, a court may similarly seek to strictly interpret terms and legal rights in favor of retail investors. The Fund may be affected by governmental action in ways that are not foreseeable, and there is a possibility that such actions could have a significant adverse effect on the Fund and its ability to achieve its investment objective. Investment Company Act Regulations The Fund is a registered closed-end management investment company and as such is subject to regulations under the Investment Company Act. Generally speaking, any contract or provision thereof that is made, or where performance involves a violation of the Investment Company Act or any rule or regulation thereunder is unenforceable by either party unless a court finds otherwise. Regulation as a “Commodity Pool” The CFTC subjects advisers to registered investment companies to regulation by the CFTC if a fund that is advised by the investment adviser either (i) invests, directly or indirectly, more than a prescribed level of its liquidation value in CFTC-regulated futures, options and swaps (“CFTC Derivatives”), or (ii) markets itself as providing investment exposure to such instruments. To the extent the Fund uses CFTC Derivatives, it intends to do so below such prescribed levels and will not market itself as a “commodity pool” or a vehicle for trading such instruments. Accordingly, the Advisor has claimed an exclusion from the definition of the term “commodity pool operator” under the Commodity Exchange Act (“CEA”) pursuant to Rule 4.5 under the CEA. The Advisor is not, therefore, subject to registration or regulation as a “commodity pool operator” under the CEA in respect of the Fund. Failures of Futures Commission Merchants and Clearing Organizations Risk The Fund is required to deposit funds to margin open positions in cleared derivative instruments (both futures and swaps) with a clearing broker registered as a “futures commission merchant” (“FCM”). The CEA requires an FCM to segregate all funds received from customers with respect to any orders for the purchase or sale of U.S. domestic futures contracts and cleared swaps from the FCM’s proprietary assets. Similarly, the CEA requires each FCM to hold in a separate secure account all funds received from customers with respect to any orders for the purchase or sale of foreign futures contracts and segregate any such funds from the funds received with respect to domestic futures contracts. However, all funds and other property received by an FCM from its customers are held by an FCM on a commingled basis in an omnibus account and amounts in excess of assets posted to the clearing organization may be invested by an FCM in certain instruments permitted under the applicable regulation. There is a risk that assets deposited by the Fund with any FCM as margin for futures contracts or commodity options may, in certain circumstances, be used to satisfy losses of other clients of the Fund’s FCM. In addition, the assets of the Fund posted as margin against both swaps and futures contracts may not be fully protected in the event of the FCM’s bankruptcy. Legal, Tax and Regulatory Risks Legal, tax and regulatory changes could occur that may have material adverse effects on the Fund. To qualify for the favorable U.S. federal income tax treatment generally accorded to RICs, the Fund must, among other things, derive in each taxable year at least 90% of its gross income from certain prescribed sources and distribute for each taxable year at least 90% of its “investment company taxable income” (generally, ordinary income plus the excess, if any, of net short-term capital gain over net long-term capital loss). If for any taxable year the Fund does not qualify as a RIC, all of its taxable income for that year (including its net capital gain) would be subject to tax at regular corporate rates without any deduction for distributions to shareholders, and such distributions would be taxable as ordinary dividends to the extent of the Fund’s current and accumulated earnings and profits. The current presidential administration has called for significant changes to U.S. fiscal, tax, trade, healthcare, immigration, foreign, and government regulatory policy. In this regard, there is significant uncertainty with respect to legislation, regulation and government policy at the federal level, as well as the state and local levels. Recent events have created a climate of heightened uncertainty and introduced new and difficult-to-quantify macroeconomic and political risks with potentially far-reaching implications. There has been a corresponding meaningful increase in the uncertainty surrounding interest rates, inflation, foreign exchange rates, trade volumes and fiscal and monetary policy. To the extent the U.S. Congress or the current presidential administration implements changes to U.S. policy, those changes may impact, among other things, the U.S. and global economy, international trade and relations, unemployment, immigration, corporate taxes, healthcare, the U.S. regulatory environment, inflation and other areas. Although the Fund cannot predict the impact, if any, of these changes to the Fund’s business, they could adversely affect the Fund’s business, financial condition, operating results and cash flows. Until the Fund knows what policy changes are made and how those changes impact the Fund’s business and the business of the Fund’s competitors over the long term, the Fund will not know if, overall, the Fund will benefit from them or be negatively affected by them. The rules dealing with U.S. federal income taxation are constantly under review by persons involved in the legislative process and by the Internal Revenue Service and the U.S. Treasury Department. Revisions in U.S. federal tax laws and interpretations of these laws could adversely affect the tax consequences of your investment . Potential Conflicts of Interest of the Advisor, Sub-Advisor and Others The investment activities of the Advisor, the Sub-Advisor and their affiliates (including BlackRock, Inc. and its subsidiaries (collectively, the “Affiliates”)), and their respective directors, officers or employees, in managing their own accounts and other accounts, may present conflicts of interest that could disadvantage the Fund and its shareholders. The Advisor and its Affiliates may engage in proprietary trading and advise accounts and other funds that have investment objectives similar to those of the Fund and/or that engage in and compete for transactions in the same or similar types of securities, currencies and other assets as are held by the Fund. Subject to the requirements of the Investment Company Act, the Advisor and its Affiliates intend to engage in such activities and may receive compensation from third parties for their services. Neither the Advisor nor any Affiliate is under any obligation to share any investment opportunity, idea or strategy with the Fund. As a result, an Affiliate may compete with the Fund for appropriate investment opportunities. The results of the Fund’s investment activities, therefore, may differ from those of an Affiliate and of other accounts managed by an Affiliate. It is possible that the Fund could sustain losses during periods in which one or more Affiliates and other accounts achieve profits on their trading for proprietary or other accounts. The opposite result is also possible. The Advisor has adopted policies and procedures designed to address potential conflicts of interest. For additional information about potential conflicts of interest and the way in which BlackRock addresses such conflicts, please see “Conflicts of Interest” and “Management of the Fund—Portfolio Management—Potential Material Conflicts of Interest” in the SAI. Defensive Investing Risk For defensive purposes, the Fund may allocate assets into cash or short-term fixed-income securities without limitation. In doing so, the Fund may succeed in avoiding losses but may otherwise fail to achieve its investment objective. Further, the value of short-term fixed-income securities may be affected by changing interest rates and by changes in credit ratings of the investments. If the Fund holds cash uninvested it will be subject to the credit risk of the depository institution holding the cash. Decision-Making Authority Risk Investors have no authority to make decisions or to exercise business discretion on behalf of the Fund, except as set forth in the Fund’s governing documents. The authority for all such decisions is generally delegated to the Board, which in turn, has delegated the day-to-day management of the Fund’s investment activities to the Advisors, subject to oversight by the Board. Management Risk The Fund is subject to management risk because it is an actively managed investment portfolio. The Advisors and the individual portfolio managers will apply investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these will produce the desired results. The Fund may be subject to a relatively high level of management risk because the Fund may invest in derivative instruments, which may be highly specialized instruments that require investment techniques and risk analyses different from those associated with equities and bonds. Valuation Risk The Fund is subject to valuation risk, which is the risk that one or more of the securities in which the Fund invests are valued at prices that the Fund is unable to obtain upon sale due to factors such as incomplete data, market instability or human error. The Advisor may use an independent pricing service or prices provided by dealers to value securities at their market value. Because the secondary markets for certain investments may be limited, such instruments may be difficult to value. See “Net Asset Value.” When market quotations are not available, the Advisor may price such investments pursuant to a number of methodologies, such as computer-based analytical modeling or individual security evaluations. These methodologies generate approximations of market values, and there may be significant professional disagreement about the best methodology for a particular type of financial instrument or different methodologies that might be used under different circumstances. In the absence of an actual market transaction, reliance on such methodologies is essential, but may introduce significant variances in the ultimate valuation of the Fund’s investments. Technological issues and/or errors by pricing services or other third-party service providers may also impact the Fund’s ability to value its investments and the calculation of the Fund’s NAV. When market quotations are not readily available or are believed by the Advisor to be unreliable, the Advisor will fair value the Fund’s investments in accordance with its policies and procedures. Fair value represents a good faith approximation of the value of an asset or liability. The fair value of an asset or liability held by the Fund is the amount the Fund might reasonably expect to receive from the current sale of that asset or the cost to extinguish that liability in an arm’s-length transaction. Fair value pricing may require determinations that are inherently subjective and inexact about the value of a security or other asset. As a result, there can be no assurance that fair value priced assets will not result in future adjustments to the prices of securities or other assets, or that fair value pricing will reflect a price that the Fund is able to obtain upon sale, and it is possible that the fair value determined for a security or other asset will be materially different from quoted or published prices, from the prices used by others for the same security or other asset and/or from the value that actually could be or is realized upon the sale of that security or other asset. For example, the Fund’s NAV could be adversely affected if the Fund’s determinations regarding the fair value of the Fund’s investments were materially higher than the values that the Fund ultimately realizes upon the disposal of such investments. Where market quotations are not readily available, valuation may require more research than for more liquid investments. In addition, elements of judgment may play a greater role in valuation in such cases than for investments with a more active secondary market because there is less reliable objective data available. Because of overall size, duration and maturities of positions held by the Fund, the value at which its investments can be liquidated may differ, sometimes significantly, from the interim valuations obtained by the Fund. In addition, the timing of liquidations may also affect the values obtained on liquidation. Securities held by the Fund may routinely trade with bid-offer spreads that may be significant. There can be no guarantee that the Fund’s investments could ultimately be realized at the Fund’s valuation of such investments. In addition, the Fund’s compliance with the asset diversification tests applicable to regulated investment companies depends on the fair market values of the Fund’s assets, and, accordingly, a challenge to the valuations ascribed by the Fund could affect its ability to comply with those tests or require it to pay penalty taxes in order to cure a violation thereof. The Fund’s NAV per share is a critical component in several operational matters including computation of advisory and services fees and determination of the price at which a tender offer will be made. Consequently, variance in the valuation of the Fund’s investments will impact, positively or negatively, the fees and expenses shareholders will pay. Reliance on the Advisor and Sub-Advisor Risk The Fund is dependent upon services and resources provided by the Advisors, and therefore the Advisors’ parent, BlackRock, Inc. The Advisors are not required to devote their full time to the business of the Fund and there is no guarantee or requirement that any investment professional or other employee of the Advisors will allocate a substantial portion of his or her time to the Fund. The loss of one or more individuals involved with the Advisors could have a material adverse effect on the performance or the continued operation of the Fund. For additional information on the Advisor, the Sub-Advisor and BlackRock, see “Management of the Fund—Investment Advisor and Sub-Advisor.” Reliance on Service Providers Risk The Fund must rely upon the performance of service providers to perform certain functions, which may include functions that are integral to the Fund’s operations and financial performance. Failure by any service provider to carry out its obligations to the Fund in accordance with the terms of its appointment, to exercise due care and skill or to perform its obligations to the Fund at all as a result of insolvency, bankruptcy or other causes could have a material adverse effect on the Fund’s performance and returns to shareholders. The termination of the Fund’s relationship with any service provider, or any delay in appointing a replacement for such service provider, could materially disrupt the business of the Fund and could have a material adverse effect on the Fund’s performance and returns to shareholders. Information Technology Systems Risk The Fund is dependent on the Advisors for certain management services as well as back-office functions. The Advisors depend on information technology systems in order to assess investment opportunities, strategies and markets and to monitor and control risks for the Fund. It is possible that a failure of some kind which causes disruptions to these information technology systems could materially limit the Advisors’ ability to adequately assess and adjust investments, formulate strategies and provide adequate risk control. Any such information technology-related difficulty could harm the performance of the Fund. Further, failure of the back-office functions of the Advisors to process trades in a timely fashion could prejudice the investment performance of the Fund. Operational and Technology Risks The Fund and the entities with which it interacts directly or indirectly are susceptible to operational and technology risks, including those related to human errors, processing errors, communication errors, systems failures, cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses for the Fund and its shareholders or impair the Fund’s operations. These entities include, but are not limited to, the Fund’s adviser, administrator, distributor, other service providers (e.g., index and benchmark providers, accountants, custodians, and transfer agents), financial intermediaries, counterparties, market makers, authorized participants, listing exchanges, other financial market operators, and governmental authorities. Operational and technology risks for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and may cause the Fund’s investments in such issuers to lose value. The Fund may incur substantial costs in order to mitigate operational and technology risks. Cybersecurity incidents can result from deliberate attacks or unintentional events against an issuer in which the Fund invests, the Fund or any of its service providers. They include, but are not limited to, gaining unauthorized access to systems, misappropriating assets or sensitive information, corrupting or destroying data, and causing operational disruption. Geopolitical tension may increase the scale and sophistication of deliberate attacks, particularly those from nation states or from entities with nation state backing. Cybersecurity incidents may result in any of the following: financial losses; interference with the Fund’s ability to calculate its NAV; disclosure of confidential information; impediments to trading; submission of erroneous trades by the Fund or erroneous subscription or redemption orders; the inability of the Fund or its service providers to transact business; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; and other legal and compliance expenses. Furthermore, cybersecurity incidents may render records of the Fund, including records relating to its assets and transactions, shareholder ownership of Fund shares, and other data integral to the Fund’s functioning, inaccessible, inaccurate or incomplete. Power outages, natural disasters, equipment malfunctions and processing errors that threaten information and technology systems relied upon by the Fund or its service providers, as well as market events that occur at a pace that overloads these systems, may also disrupt business operations or impact critical data. In addition, the risks of increased use of AI technologies, such as machine learning, include data risk, transparency risk, and operational risk. The AI technologies, which are generally highly reliant on the collection and analysis of large amounts of data, may incorporate biased or inaccurate data, and it is not possible or practicable to incorporate all relevant data into such technologies. The output or results of any such AI technologies may therefore be incomplete, erroneous, distorted or misleading. Further, AI tools may lack transparency as to how data is utilized and how outputs are generated. AI technologies may also allow the unintended introduction of vulnerabilities into infrastructures and applications. The Fund and its shareholders could be negatively impacted as a result of these risks associated with AI technologies. AI technologies and their current and potential future applications, and the regulatory frameworks within which they operate, continue to quickly evolve, and it is impossible to anticipate the full scope of future AI capabilities or rules and the associated risks to the Fund. While the Fund’s service providers are required to have appropriate operational, information security and cybersecurity risk management policies and procedures, their methods of risk management may differ from those of the Fund in the setting of priorities, the personnel and resources available or the effectiveness of relevant controls. The Fund and its adviser seek to reduce these risks through controls, procedures and oversight, including establishing business continuity plans and risk management systems. However, there are inherent limitations in such plans and systems, including the possibility that certain risks that may affect the Fund have not been identified or may emerge in the future; that such plans and systems may not completely eliminate the occurrence or mitigate the effects of operational or information security disruptions or failures or of cybersecurity incidents; or that prevention and remediation efforts will not be successful or that incidents will go undetected. The Fund cannot control the systems, information security or other cybersecurity of the issuers in which it invests or its service providers, counterparties, and other third parties whose activities affect the Fund. Lastly, the regulatory climate governing cybersecurity and data protection is developing quickly and may vary considerably across jurisdictions. Regulators continue to develop new rules and standards related to cybersecurity and data protection. Compliance with evolving regulations can be demanding and costly, requiring substantial resources to monitor and implement required changes. Misconduct of Employees and of Service Providers Risk Misconduct or misrepresentations by employees of the Advisor, the Sub-Advisor or the Fund’s service providers could cause significant losses to the Fund. Employee misconduct may include binding the Fund to transactions that exceed authorized limits or present unacceptable risks and unauthorized trading activities, concealing unsuccessful trading activities (which, in any case, may result in unknown and unmanaged risks or losses) or making misrepresentations regarding any of the foregoing. Losses could also result from actions by the Fund’s service providers, including, without limitation, failing to recognize trades and misappropriating assets. In addition, employees and service providers may improperly use or disclose confidential information, which could result in litigation or serious financial harm, including limiting the Fund’s business prospects or future marketing activities. Despite the Advisors’ due diligence efforts, misconduct and intentional misrepresentations may be undetected or not fully comprehended, thereby potentially undermining the Advisors’ due diligence efforts. As a result, no assurances can be given that the due diligence performed by the Advisors will identify or prevent any such misconduct. Special Risks for Holders of Rights There is a risk that performance of the Fund may result in the common shares purchasable upon exercise of the rights being less attractive to investors at the conclusion of the subscription period. This may reduce or eliminate the value of the rights. Investors who receive rights may find that there is no market to sell rights they do not wish to exercise. If investors exercise only a portion of the rights, common shares may trade at less favorable prices than larger offerings for similar securities. Portfolio Turnover Risk The Fund’s annual portfolio turnover rate may vary greatly from year to year, as well as within a given year. Portfolio turnover rate is not considered a limiting factor in the execution of investment decisions for the Fund. A higher portfolio turnover rate results in correspondingly greater brokerage commissions and other transactional expenses that are borne by the Fund. High portfolio turnover may result in an increased realization of net short-term capital gains by the Fund which, when distributed to common shareholders, will be taxable as ordinary income. Additionally, in a declining market, portfolio turnover may create realized capital losses. Anti-Takeover Provisions Risk The Fund’s Charter and Bylaws include provisions that could limit the ability of other entities or persons to acquire control of the Fund or convert the Fund to open-end status or to change the composition of the Board. Such provisions may limit the ability of shareholders to sell their shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. See “Certain Provisions in the Charter and Bylaws.” HOW THE FUND MANAGES RISK Investment Limitations The Fund has adopted certain investment limitations designed to limit investment risk. Some of these limitations are fundamental and thus may not be changed without the approval of the holders of a majority of the outstanding common shares. See “Investment Objective and Policies—Investment Restrictions” in the SAI. The restrictions and other limitations set forth throughout this Prospectus and in the SAI apply only at the time of purchase of securities and will not be considered violated unless an excess or deficiency occurs or exists immediately after and as a result of the acquisition of securities. Management of Investment Portfolio and Capital Structure to Limit Leverage Risk The Fund may take certain actions if short-term interest rates increase or market conditions otherwise change (or the Fund anticipates such an increase or change) and any leverage the Fund may have outstanding begins (or is expected) to adversely affect common shareholders. In order to attempt to offset such a negative impact of any outstanding leverage on common shareholders, the Fund may shorten the average maturity of its investment portfolio (by investing in short-term securities) or may reduce any indebtedness that it may have incurred. The success of any such atte mp t to limit leverage risk depends on the Advisors’ ability to accurately predict interest rate or other market changes. Because of the difficulty of making such predictions, the Fund may never attempt to manage its capital structure in the manner described in this paragraph. If market conditions suggest that employing leverage, or employing additional leverage if the Fund already has outstanding leverage, would be beneficial, the Fund may enter into one or more credit facilities, increase any existing credit facilities, sell preferred shares or engage in additional leverage transactions, subject to the restrictions of the Investment Company Act. Strategic Transactions The Fund may use certain Strategic Transactions designed to limit the risk of price fluctuations of securities and to preserve capital. These Strategic Transactions include using swaps, financial futures contracts, options on financial futures or options based on either an index of long-term securities, or on securities whose prices, in the opinion of the Advisors, correlate with the prices of the Fund’s investments. There can be no assurance that Strategic Transactions will be used or used effectively to limit risk, and Strategic Transactions may be subject to their own risks. |  |  |  |  |  |  |  |  |  |
Effects of Leverage [Text Block] |  | Effects of Leverage Assuming that leverage will represent approximately 20.30% of the Fund’s Managed Assets and that the Fund will bear expenses relating to that leverage at an average annual rate of 1.81%, the income generated by the Fund’s portfolio (net of estimated expenses) must exceed 0.37% in order to cover the expenses specifically related to the Fund’s use of leverage. Of course, these numbers are merely estimates used for illustration. Actual leverage expenses will vary frequently and may be significantly higher or lower than the rate estimated above. The following table is furnished in response to requirements of the SEC. It is designed to illustrate the effect of leverage on common share total return, assuming investment portfolio total returns (comprised of income and changes in the value of investments held in the Fund’s portfolio) of (10)%, (5)%, 0%, 5% and 10%. These assumed investment portfolio returns are hypothetical figures and are not necessarily indicative of the investment portfolio returns experienced or expected to be experienced by the Fund. The table further reflects the use of leverage representing 20.30% of the Fund’s Managed Assets and an assumed annual cost of leverage of 1.81%.
Assumed Portfolio Total Return (Net of Expenses) |  |  | (10.00)% |  |  |  | (5.00)% |  |  |  | 0% |  |  |  | 5.00% |  |  |  | 10.00% |  |  |  |  |
Common Share Total Return |  |  | (13.01)% |  |  |  | (6.74)% |  |  |  | (0.46)% |  |  |  | 5.81% |  |  |  | 12.09% |  |  |  |  |
Common share total return is composed of two elements: the common share dividends paid by the Fund (the amount of which is largely determined by the net investment income of the Fund after paying for any leverage used by the Fund) and gains or losses on the value of the securities the Fund owns. As required by SEC rules, the table assumes that the Fund is more likely to suffer capital losses than to enjoy capital appreciation. For example, to assume a total return of 0% the Fund must assume that the interest it receives on its investments is entirely offset by losses in the value of those securities. |  |  |  |  |  |  |  |  |  |
Effects of Leverage [Table Text Block] |  | The following table is furnished in response to requirements of the SEC. It is designed to illustrate the effect of leverage on common share total return, assuming investment portfolio total returns (comprised of income and changes in the value of investments held in the Fund’s portfolio) of (10)%, (5)%, 0%, 5% and 10%. These assumed investment portfolio returns are hypothetical figures and are not necessarily indicative of the investment portfolio returns experienced or expected to be experienced by the Fund. The table further reflects the use of leverage representing 20.30% of the Fund’s Managed Assets and an assumed annual cost of leverage of 1.81%.
Assumed Portfolio Total Return (Net of Expenses) |  |  | (10.00)% |  |  |  | (5.00)% |  |  |  | 0% |  |  |  | 5.00% |  |  |  | 10.00% |  |  |  |  |
Common Share Total Return |  |  | (13.01)% |  |  |  | (6.74)% |  |  |  | (0.46)% |  |  |  | 5.81% |  |  |  | 12.09% |  |  |  |  |
Return at Minus Ten [Percent] |  | (13.01%) |  |  |  |  |  |  |  |  |  |
Return at Minus Five [Percent] |  | (6.74%) |  |  |  |  |  |  |  |  |  |
Return at Zero [Percent] |  | (0.46%) |  |  |  |  |  |  |  |  |  |
Return at Plus Five [Percent] |  | 5.81% |  |  |  |  |  |  |  |  |  |
Return at Plus Ten [Percent] |  | 12.09% |  |  |  |  |  |  |  |  |  |
Effects of Leverage, Purpose [Text Block] |  | The following table is furnished in response to requirements of the SEC. It is designed to illustrate the effect of leverage on common share total return, assuming investment portfolio total returns (comprised of income and changes in the value of investments held in the Fund’s portfolio) of (10)%, (5)%, 0%, 5% and 10%. These assumed investment portfolio returns are hypothetical figures and are not necessarily indicative of the investment portfolio returns experienced or expected to be experienced by the Fund. The table further reflects the use of leverage representing 20.30% of the Fund’s Managed Assets and an assumed annual cost of leverage of 1.81%. |  |  |  |  |  |  |  |  |  |
Share Price [Table Text Block] |  |
|  | NYSE Market Price Per Common Share |  |  | NAV per Common Share on Date of Market Price |  |  | Premium/ (Discount) on Date of Market Price |  |  | Trading |
During Quarter Ended |  | High |  |  | Low |  |  | High |  |  | Low |  |  | High |  |  | Low |  |  | Volume |
June 30, 2025 |  |  | $  11.98 |  |  |  | $  11.28 |  |  |  | $  12.13 |  |  |  | $  11.80 |  |  |  | (1.24)% |  |  |  | (4.41)% |  |  |  | 5,319,422 |
March 31, 2025 |  |  | $  11.85 |  |  |  | $  11.32 |  |  |  | $  11.99 |  |  |  | $  11.60 |  |  |  | (1.17)% |  |  |  | (2.41)% |  |  |  | 3,781,973 |
December 31, 2024 |  |  | $  12.53 |  |  |  | $  11.39 |  |  |  | $  12.70 |  |  |  | $  11.76 |  |  |  | (1.34)% |  |  |  | (3.15)% |  |  |  | 3,964,773 |
September 30, 2024 |  |  | $  12.61 |  |  |  | $  11.77 |  |  |  | $  12.82 |  |  |  | $  11.97 |  |  |  | (1.64)% |  |  |  | (1.67)% |  |  |  | 4,057,128 |
June 30, 2024 |  |  | $  11.93 |  |  |  | $  11.12 |  |  |  | $  12.06 |  |  |  | $  11.75 |  |  |  | (1.08)% |  |  |  | (5.36)% |  |  |  | 4,052,428 |
March 31, 2024 |  |  | $  12.36 |  |  |  | $  11.73 |  |  |  | $  12.73 |  |  |  | $  12.19 |  |  |  | (2.95)% |  |  |  | (3.77)% |  |  |  | 3,803,044 |
December 31, 2023 |  |  | $  12.60 |  |  |  | $  10.56 |  |  |  | $  12.81 |  |  |  | $  11.52 |  |  |  | (1.64)% |  |  |  | (8.33)% |  |  |  | 4,901,930 |
September 30, 2023 |  |  | $  12.32 |  |  |  | $  11.15 |  |  |  | $  12.83 |  |  |  | $  11.95 |  |  |  | (3.98)% |  |  |  | (6.69)% |  |  |  | 3,041,993 |
June 30, 2023 |  |  | $  12.87 |  |  |  | $  12.12 |  |  |  | $  13.56 |  |  |  | $  12.72 |  |  |  | (5.09)% |  |  |  | (4.72)% |  |  |  | 3,324,123 |
March 31, 2023 |  |  | $  13.27 |  |  |  | $  12.39 |  |  |  | $  13.73 |  |  |  | $  12.97 |  |  |  | (3.35)% |  |  |  | (4.47)% |  |  |  | 3,858,408 |
Capital Stock, Long-Term Debt, and Other Securities [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Outstanding Securities [Table Text Block] |  | The following table provides the amount of the Fund’s authorized shares and the amount of shares issued and outstanding as of September 11, 2025.
Title of Class |  | Amount Authorized |  |  | Amount Held by Fund or for its Account |  |  | Amount Outstanding Exclusive of Amount Held by Fund |
Common Shares |  |  | 200,000,000 |  |  |  | 0 |  |  |  | 24,291,714 |
General Risks [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | General Risks Please refer to the section of the Fund’s most recent annual report on Form N-CSR entitled “Investment Objectives, Policies and Risks—Risk Factors” , which is incorporated by reference herein, for a discussion of the general risks of investing in the Fund. |  |  |  |  |  |  |  |  |  |
WhenIssued Forward Commitment and Delayed Delivery Transactions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | When-Issued, Forward Commitment and Delayed Delivery Transactions Risk The Fund may purchase securities on a when-issued basis (including on a forward commitment or “TBA” (to be announced) basis) and may purchase or sell securities for delayed delivery. When-issued and delayed delivery transactions occur when securities are purchased or sold by the Fund with payment and delivery taking place in the future to secure an advantageous yield or price. Securities purchased on a when-issued or delayed delivery basis may expose the Fund to counterparty risk of default as well as the risk that securities may experience fluctuations in value prior to their actual delivery. The Fund will not accrue income with respect to a when-issued or delayed delivery security prior to its stated delivery date. Purchasing securities on a when-issued or delayed delivery basis can involve the additional risk that the price or yield available in the market when the delivery takes place may not be as favorable as that obtained in the transaction itself. |  |  |  |  |  |  |  |  |  |
Collateralized Debt Obligations Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Collateralized Debt Obligations Risk In addition to the typical risks associated with fixed-income securities and asset-backed securities, collateralized debt obligations (“CDOs”), including collateralized loan obligations (“CLOs”), carry additional risks including, but not limited to: (i) the possibility that distributions from collateral securities will not be adequate to make interest or other payments; (ii) the risk that the collateral may default or decline in value or be downgraded, if rated by a nationally recognized statistical rating organization; (iii) the Fund may invest in tranches of CDOs that are subordinate to other tranches; (iv) the structure and complexity of the transaction and the legal documents could lead to disputes among investors regarding the characterization of proceeds; (v) the investment return achieved by the Fund could be significantly different than those predicted by financial models; (vi) the lack of a readily available secondary market for CDOs; (vii) the risk of forced “fire sale” liquidation due to technical defaults such as coverage test failures; and (viii) the CDO’s manager may perform poorly. |  |  |  |  |  |  |  |  |  |
Dollar Roll Transactions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Dollar Roll Transactions Risk Dollar roll transactions involve the risk that the market value of the securities the Fund is required to purchase may decline below the agreed upon repurchase price of those securities. If the broker/dealer to which the Fund sells securities becomes insolvent, the Fund’s right to purchase or repurchase securities may be restricted. Successful use of dollar rolls may depend upon the Advisor’s ability to predict correctly interest rates and prepayments. There is no assurance that dollar rolls can be successfully employed. These transactions may involve leverage. |  |  |  |  |  |  |  |  |  |
Short Sales Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Short Sales Risk Short-selling involves selling securities which may or may not be owned and borrowing the same securities for delivery to the purchaser, with an obligation to replace the borrowed securities at a later date. If the price of the security sold short increases between the time of the short sale and the time the Fund replaces the borrowed security, the Fund will incur a loss; conversely, if the price declines, the Fund will realize a capital gain. Any gain will be decreased, and any loss will be increased, by the transaction costs incurred by the Fund, including the costs associated with providing collateral to the broker-dealer (usually cash and liquid securities) and the maintenance of collateral with its custodian. Although the Fund’s gain is limited to the price at which it sold the security short, its potential loss is theoretically unlimited. Short-selling necessarily involves certain additional risks. However, if the short seller does not own the securities sold short (an uncovered short sale), the borrowed securities must be replaced by securities purchased at market prices in order to close out the short position, and any appreciation in the price of the borrowed securities would result in a loss. Uncovered short sales expose the Fund to the risk of uncapped losses until a position can be closed out due to the lack of an upper limit on the price to which a security may rise. Purchasing securities to close out the short position can itself cause the price of the securities to rise further, thereby exacerbating the loss. There is the risk that the securities borrowed by the Fund in connection with a short-sale must be returned to the securities lender on short notice. If a request for return of borrowed securities occurs at a time when other short-sellers of the security are receiving similar requests, a “short squeeze” can occur, and the Fund may be compelled to replace borrowed securities previously sold short with purchases on the open market at the most disadvantageous time, possibly at prices significantly in excess of the proceeds received at the time the securities were originally sold short. |  |  |  |  |  |  |  |  |  |
Investment Companies and ETFs Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Investment Companies and ETFs Risk Subject to the limitations set forth in the Investment Company Act and the rules thereunder, the Fund may acquire shares in other investment companies and in ETFs and business development companies (“BDCs”), some of which may be affiliated investment companies. The market value of the shares of other investment companies and ETFs may differ from their NAV. As an investor in investment companies, including ETFs and BDCs, the Fund would bear its ratable share of that entity’s expenses, including its investment advisory and administration fees, while continuing to pay its own advisory and administration fees and other expenses (to the extent not offset by the Advisor through waivers). As a result, shareholders will be absorbing duplicate levels of fees with respect to investments in other investment companies, including ETFs and BDCs (to the extent not offset by the Advisor through waivers). The securities of other investment companies, including ETFs and BDCs, in which the Fund may invest may be leveraged. As a result, the Fund may be indirectly exposed to leverage through an investment in such securities. An investment in securities of other investment companies, including ETFs and BDCs, that use leverage may expose the Fund to higher volatility in the market value of such securities and the possibility that the Fund’s long-term returns on such securities (and, indirectly, the long-term returns of shares of the Fund) will be diminished. The portfolios of ETFs are generally not actively managed and may be affected by a general decline in market segments relating to its index. An ETF typically invests in securities included in, or representative of, its index regardless of their investment merits and does not attempt to take defensive positions in declining markets. |  |  |  |  |  |  |  |  |  |
Securities Lending Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Securities Lending Risk Securities lending involves exposure to certain risks, including operational risk (i.e., the risk of losses resulting from problems in the settlement and accounting process), “gap” risk (i.e., the risk of a mismatch between the return on cash collateral reinvestments and the fees the Fund has agreed to pay a borrower), foreign exchange risk (i.e., the risk of a shortfall at default when a cash collateral investment is denominated in a currency other than the currency of the assets being loaned due to movements in foreign exchange rates), and credit, legal, counterparty and market risks (including the risk that market events, including but not limited to corporate actions, could lead the Fund to lend securities that are trading at a premium due to increased demand, or to recall loaned securities or to lend less or not at all, which could lead to reduced securities lending revenue). If the Fund were to lend out securities that are subject to a corporate action and commit to the borrower a particular election as determined by the Advisor, the benefit the Fund would receive in respect of committing to such election may or may not be less than the benefit the Fund would have received from making a different election in such corporate action. If a securities lending counterparty were to default, the Fund would be subject to the risk of a possible delay in receiving collateral or in recovering the loaned securities, or to a possible loss of rights in the collateral. In the event a borrower does not return the Fund’s securities as agreed, the Fund’s ability to participate in a corporate action event may be impacted, or the Fund may experience losses if the proceeds received from liquidating the collateral do not at least equal the value of the loaned security at the time the collateral is liquidated, plus the transaction costs incurred in purchasing replacement securities. This latter event could trigger adverse tax consequences for the Fund. The Fund could lose money if its short-term investment of the collateral declines in value over the period of the loan. Substitute payments received by the Fund representing dividends paid on securities loaned out by the Fund will not be considered qualified dividend income, and distributions by the Fund of such substitute payments will not constitute qualified dividend income. Additionally, substitute payments received by the Fund representing qualified REIT dividends paid on REIT securities loaned out by the Fund will not be considered qualified REIT dividends, and distributions by the Fund of such substitute payments will not be eligible for a 20% deduction currently available for ordinary REIT dividends paid to non-corporate shareholders provided certain other requirements are satisfied. The securities lending agent will take into account the tax effects on shareholders caused by these differences in connection with the Fund’s securities lending program. Substitute payments received on tax-exempt securities loaned out will not be tax-exempt income. There could also be changes in the status of issuers under applicable laws and regulations, including tax regulations, that may impact the regulatory or tax treatment of loaned securities and could, for example, result in a delay in the payment of dividend equivalent payments owed to the Fund (as permitted by applicable law). Regulations adopted by global prudential regulators require certain bank-regulated counterparties and certain of their affiliates to include in certain financial contracts, including many securities lending agreements, terms that delay or restrict the rights of counterparties, such as the Fund, to terminate such agreements, foreclose upon collateral, exercise other default rights or restrict transfers of credit support in the event that the counterparty and/or its affiliates are subject to certain types of resolution or insolvency proceedings. It is possible that these requirements, as well as potential additional government regulation and other developments in the market, could adversely affect the Fund’s ability to terminate existing securities lending agreements or to realize amounts to be received under such agreements. Prudential regulation may also favor lenders that can provide additional protections, such as liens that are exercisable upon lender default, to bank borrowers. The Fund may provide additional protections to bank borrowers, where permitted pursuant to the Fund’s investment policies and if the Advisor believes doing so is in the best interest of the Fund. |  |  |  |  |  |  |  |  |  |
Swaps Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Swaps Risk Swaps are a type of derivative. Swap agreements involve the risk that the party with which the Fund has entered into the swap will default on its obligation to pay the Fund and the risk that the Fund will not be able to meet its obligations to pay the other party to the agreement. In order to seek to hedge the value of the Fund’s portfolio, to hedge against increases in the Fund’s cost associated with interest payments on any outstanding borrowings or to seek to increase the Fund’s return, the Fund may enter into swaps, including interest rate swap, total return swap (sometimes referred to as a “contract for difference”) and/or credit default swap transactions. In interest rate swap transactions, there is a risk that yields will move in the direction opposite of the direction anticipated by the Fund, which would cause the Fund to make payments to its counterparty in the transaction that could adversely affect Fund performance. In addition to the risks applicable to swaps generally (including counterparty risk, high volatility, illiquidity risk and credit risk), credit default swap transactions involve special risks because they are difficult to value, are highly susceptible to liquidity and credit risk, and generally pay a return to the party that has paid the premium only in the event of an actual default by the issuer of the underlying obligation (as opposed to a credit downgrade or other indication of financial difficulty). The United States, the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the “Dodd-Frank Act”), requires that certain derivatives with U.S. persons must be executed on a regulated market and a substantial portion of OTC derivatives must be submitted for clearing to regulated clearinghouses. As a result, swap transactions entered into by the Fund may become subject to various requirements applicable to swaps under the Dodd-Frank Act, including clearing, exchange-execution, reporting and recordkeeping requirements, which may make it more difficult and costly for the Fund to enter into swap transactions and may also render certain strategies in which the Fund might otherwise engage impossible or so costly that they will no longer be economical to implement. Furthermore, the number of counterparties that may be willing to enter into swap transactions with the Fund may also be limited if the swap transactions with the Fund are subject to the swap regulation under the Dodd-Frank Act. Credit default and total return swap agreements may effectively add leverage to the Fund’s portfolio because, in addition to its Managed Assets, the Fund would be subject to investment exposure on the notional amount of the swap in excess of any premium and margin required to establish and maintain the position. Total return swap agreements are subject to market risk as well as the risk that a counterparty will default on its payment obligations to the Fund thereunder. The Fund is not required to enter into swap transactions for hedging purposes or to enhance income or gain and may choose not to do so. In addition, the swaps market is subject to a changing regulatory environment. It is possible that regulatory or other developments in the swaps market could adversely affect the Fund’s ability to successfully use swaps. |  |  |  |  |  |  |  |  |  |
Inflation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Inflation Risk Inflation risk is the risk that the value of assets or income from investment will be worth less in the future, as inflation decreases the value of money. Inflation rates may change frequently and drastically as a result of various factors, including unexpected shifts in the domestic or global economy. As inflation increases, the real value of the common shares and distributions on those shares can decline. In addition, during any periods of rising inflation, interest rates on any borrowings by the Fund would likely increase, which would tend to further reduce returns to the holders of common shares. |  |  |  |  |  |  |  |  |  |
Deflation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Deflation Risk Deflation risk is the risk that prices throughout the economy decline over time, which may have an adverse effect on the market valuation of companies, their assets and their revenues. In addition, deflation may have an adverse effect on the creditworthiness of issuers and may make issuer default more likely, which may result in a decline in the value of the Fund’s portfolio. |  |  |  |  |  |  |  |  |  |
Risk Associated with Recent Market Events [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Risk Associated with Recent Market Events Although interest rates were unusually low in recent years in the U.S. and abroad, in 2022, the Federal Reserve and certain foreign central banks raised interest rates as part of their efforts to address rising inflation. The Federal Reserve and certain foreign central banks have started to lower interest rates, though economic or other factors, such as inflation, could stop such changes. It is difficult to accurately predict the pace at which interest rates might change, the timing, frequency or magnitude of any such changes in interest rates, or when such changes might stop or again reverse course. Additionally, various economic and political factors could cause the Federal Reserve or other foreign central banks to change their approach in the future and such actions may result in an economic slowdown both in the U.S. and abroad. Unexpected changes in interest rates could lead to significant market volatility or reduce liquidity in certain sectors of the market. Deteriorating economic fundamentals may, in turn, increase the risk of default or insolvency of particular issuers, negatively impact market value, cause credit spreads to widen, and reduce bank balance sheets. Any of these could cause an increase in market volatility, reduce liquidity across various markets or decrease confidence in the markets, which could negatively affect the value of debt instruments held by the Fund and result in a negative impact on the Fund’s performance. See “—Inflation Risk.” Recent policy initiatives undertaken by the U.S. government have the potential to impact international relations, trade agreements and the overall regulatory environment in ways that could create uncertainty and instability in domestic and global markets, and could adversely affect the investment performance of the Fund. In particular, actions taken by the U.S. government in respect of international trade relations could lead to trade wars, increased costs for imported goods, disruptions in supply chains, reduced foreign investment, and instability in regions where the Fund invests. Political and diplomatic events within the United States, including a contentious domestic political environment, changes in political party control of one or more branches of the U.S. Government, the U.S. Government’s inability at times to agree on a long-term budget and deficit reduction plan, the threat of a U.S. Government shutdown, and disagreements over, or threats not to increase, the U.S. Government’s borrowing limit (or “debt ceiling”), as well as political and diplomatic events abroad, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. A downgrade of the ratings of U.S. Government debt obligations, or concerns about the U.S. Government’s credit quality in general, could have a substantial negative effect on the U.S. and global economies. For example, concerns about the U.S. Government’s credit quality may cause increased volatility in the stock and bond markets, higher interest rates, reduced prices and liquidity of U.S. Treasury securities, and/or increased costs of various kinds of debt. Moreover, although the U.S. Government has honored its credit obligations, there remains a possibility that the United States could default on its obligations. The consequences of such an unprecedented event are impossible to predict, but it is likely that a default by the United States would be highly disruptive to the U.S. and global securities markets and could significantly impair the value of the Fund’s investments. In recent years, some countries, including the United States, have adopted more protectionist trade policies. Slowing global economic growth, the rise in protectionist trade policies, inflationary pressures, changes to some major international trade agreements, risks associated with the trade agreements between countries and regions, including the U.S. and other foreign nations, political or economic dysfunction within some countries or regions, including the U.S., and dramatic changes in commodity and currency prices could affect the economies of many nations in ways that cannot necessarily be foreseen at the present time. In addition, if the U.S. dollar continues to be strong, it may decrease foreign demand for U.S. assets, which could have a negative impact on certain issuers and/or industries. |  |  |  |  |  |  |  |  |  |
Reference Rate Replacement Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Reference Rate Replacement Risk The Fund may be exposed to financial instruments that recently transitioned from, or continue to be tied to, the London Interbank Offered Rate (“LIBOR”) to determine payment obligations, financing terms, hedging strategies or investment value. The United Kingdom’s Financial Conduct Authority (“FCA”), which regulates LIBOR, has ceased publishing all LIBOR settings. In April 2023, however, the FCA announced that some USD LIBOR settings would continue to be published under a synthetic methodology until September 30, 2024 for certain legacy contracts. After September 30, 2024, the remaining synthetic LIBOR settings ceased to be published, and all LIBOR settings have permanently ceased. The Secured Overnight Financing Rate (“SOFR”) is a broad measure of the cost of borrowing cash overnight collateralized by U.S. Treasury securities in the repurchase agreement (“repo”) market and has been used increasingly on a voluntary basis in new instruments and transactions. Under U.S. regulations that implement a statutory fallback mechanism to replace LIBOR, benchmark rates based on SOFR have replaced LIBOR in certain financial contracts. Neither the effect of the LIBOR transition process nor its ultimate succ ess can yet be known. While some existing LIBOR-based instruments may contemplate a scenario where LIBOR is no longer available by providing for an alternative rate-setting methodology, there may be significant uncertainty regarding the effectiveness of any such alternative methodologies to replicate LIBOR. Not all existing LIBOR-based instruments may have alternative rate-setting provisions and there remains uncertainty regarding the willingness and ability of issuers to add alternative rate-setting provisions in certain existing instruments. Parties to contracts, securities or other instruments using LIBOR may disagree on transition rates or the application of transition regulation, potentially resulting in uncertainty of performance and the possibility of litigation. The Fund may have instruments linked to other interbank offered rates that may also cease to be published in the future. |  |  |  |  |  |  |  |  |  |
Market Disruption and Geopolitical Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Market Disruption and Geopolitical Risk The occurrence of events similar to those in recent years, such as the aftermath of the war in Iraq, instability in Afghanistan, Pakistan, Egypt, Libya, Syria and the Middle East, international war or conflict (including the Israel-Hamas war), new and ongoing epidemics and pandemics of infectious diseases and other global health events, natural/environmental disasters, terrorist attacks in the United States and around the world, social and political discord, debt crises (such as the Greek crisis), sovereign debt downgrades, the Russian invasion of Ukraine, increasingly strained relations between the United States and a number of foreign countries, including historical adversaries, such as North Korea, Iran, China and Russia, and the international community generally, new and continued political unrest in various countries, such as Venezuela and Spain, the exit or potential exit of one or more countries from the EU or the EMU, and continued changes in the balance of political power among and within the branches of the U.S. Government, among others, may result in market volatility, may have long term effects on the U.S. and worldwide financial markets, and may cause further economic uncertainties in the United States and worldwide. Russia launched a large-scale invasion of Ukraine on February 24, 2022. The extent and duration of the military action, resulting sanctions and resulting future market disruptions, including declines in its stock markets and the value of the ruble against the U.S. dollar, in the region are impossible to predict, but could be significant. Any such disruptions caused by Russian military action or other actions (including cyberattacks and espionage) or resulting actual and threatened responses to such activity, including purchasing and financing restrictions, boycotts or changes in consumer or purchaser preferences, sanctions, tariffs or cyberattacks on the Russian government, Russian companies or Russian individuals, including politicians, could have a severe adverse effect on Russia and the European region, including significant negative impacts on the Russian economy, the European economy and the markets for certain securities and commodities, such as oil and natural gas, and may likely have collateral impacts on such sectors globally as well as other sectors. How long such military action and related events will last cannot be predicted. Trade tensions between the United States and China have led to concerns about economic stability and could have an adverse impact on global economic conditions. The United States and China have each been implementing increased tariffs on imports from the other, and the United States has also adopted certain targeted measures such as export controls or sanctions implicating Chinese companies and officials. While certain trade agreements have been agreed between the two countries, there remains much uncertainty as to whether the trade negotiations between the United States and China will be successful and how the trade war between the United States and China will progress. Uncertainty regarding the outcome of the trade tensions and the potential for a trade war could cause the U.S. dollar to decline against safe haven currencies, such as the Japanese yen and the Euro. Events such as these and their consequences are difficult to predict and it is unclear whether further tariffs may be imposed or other escalating actions may be taken in the future. If the trade war between the United States and China continues or escalates, or if additional tariffs or trade restrictions are implemented by the United States, China or other countries in connection with a global trade war, there could be material adverse effects on the global economy, and the Fund and its portfolio investments could be materially and adversely affected. On January 31, 2020, the United Kingdom officially left the European Union (Brexit), subject to a transitional period that ended December 31, 2020. The United Kingdom and European Union have reached an agreement on the terms of their future trading relationship effective January 1, 2021, which principally relates to the trading of goods rather than services, including financial services. Further discussions are to be held between the United Kingdom and the European Union in relation to matters not covered by the trade agreement, such as financial services. The Fund faces risks associated with the potential uncertainty and consequences that may follow Brexit, including with respect to volatility in exchange rates and interest rates. Brexit could adversely affect European or worldwide political, regulatory, economic or market conditions and could contribute to instability in global political institutions, regulatory agencies and financial markets. Brexit has also led to legal uncertainty and could lead to politically divergent national laws and regulations as a new relationship between the United Kingdom and European Union is defined and the United Kingdom determines which European Union laws to replace or replicate. Any of these effects of Brexit could adversely affect any of the companies to which the Fund has exposure and any other assets that the Fund invests in. The political, economic and legal consequences of Brexit are not yet known. In the short term, financial markets may experience heightened volatility, particularly those in the United Kingdom and Europe, but possibly worldwide. The United Kingdom and Europe may be less stable than they have been in recent years, and investments in the United Kingdom and the European Union may be difficult to value or subject to greater or more frequent volatility. In the longer term, there is likely to be a period of significant political, regulatory and commercial uncertainty as the United Kingdom continues to negotiate the terms of its future trading relationship with the European Union. Cybersecurity incidents affecting particular companies or industries may adversely affect the economies of particular countries, regions or parts of the world in which the Fund invests. The occurrence of any of these above events could have a significant adverse impact on the value and risk profile of the Fund’s portfolio. The Fund does not know how long the securities markets may be affected by similar events and cannot predict the effects of similar events in the future on the U.S. economy and securities markets. There can be no assurance that similar events and other market disruptions will not have other material and adverse implications. |  |  |  |  |  |  |  |  |  |
Regulation and Government Intervention Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Regulation and Government Intervention Risk Federal, state, and other governments, their regulatory agencies or self-regulatory organizations may take actions that affect the regulation of the issuers in which the Fund invests in ways that are unforeseeable. Legislation or regulation may also change the way in which the Fund is regulated. Such legislation or regulation could limit or preclude the Fund’s ability to achieve its investment objective. In light of popular, political and judicial focus on finance related consumer protection, financial institution practices are also subject to greater scrutiny and criticism generally. In the case of transactions between financial institutions and the general public, there may be a greater tendency toward strict interpretation of terms and legal rights in favor of the consuming public, particularly where there is a real or perceived disparity in risk allocation and/or where consumers are perceived as not having had an opportunity to exercise informed consent to the transaction. In the event of conflicting interests between retail investors holding common shares of a closed-end investment company such as the Fund and a large financial institution, a court may similarly seek to strictly interpret terms and legal rights in favor of retail investors. The Fund may be affected by governmental action in ways that are not foreseeable, and there is a possibility that such actions could have a significant adverse effect on the Fund and its ability to achieve its investment objective. Investment Company Act Regulations The Fund is a registered closed-end management investment company and as such is subject to regulations under the Investment Company Act. Generally speaking, any contract or provision thereof that is made, or where performance involves a violation of the Investment Company Act or any rule or regulation thereunder is unenforceable by either party unless a court finds otherwise. |  |  |  |  |  |  |  |  |  |
Failures of Futures Commission Merchants and Clearing Organizations Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Failures of Futures Commission Merchants and Clearing Organizations Risk The Fund is required to deposit funds to margin open positions in cleared derivative instruments (both futures and swaps) with a clearing broker registered as a “futures commission merchant” (“FCM”). The CEA requires an FCM to segregate all funds received from customers with respect to any orders for the purchase or sale of U.S. domestic futures contracts and cleared swaps from the FCM’s proprietary assets. Similarly, the CEA requires each FCM to hold in a separate secure account all funds received from customers with respect to any orders for the purchase or sale of foreign futures contracts and segregate any such funds from the funds received with respect to domestic futures contracts. However, all funds and other property received by an FCM from its customers are held by an FCM on a commingled basis in an omnibus account and amounts in excess of assets posted to the clearing organization may be invested by an FCM in certain instruments permitted under the applicable regulation. There is a risk that assets deposited by the Fund with any FCM as margin for futures contracts or commodity options may, in certain circumstances, be used to satisfy losses of other clients of the Fund’s FCM. In addition, the assets of the Fund posted as margin against both swaps and futures contracts may not be fully protected in the event of the FCM’s bankruptcy. |  |  |  |  |  |  |  |  |  |
Legal Tax and Regulatory Risks [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Legal, Tax and Regulatory Risks Legal, tax and regulatory changes could occur that may have material adverse effects on the Fund. To qualify for the favorable U.S. federal income tax treatment generally accorded to RICs, the Fund must, among other things, derive in each taxable year at least 90% of its gross income from certain prescribed sources and distribute for each taxable year at least 90% of its “investment company taxable income” (generally, ordinary income plus the excess, if any, of net short-term capital gain over net long-term capital loss). If for any taxable year the Fund does not qualify as a RIC, all of its taxable income for that year (including its net capital gain) would be subject to tax at regular corporate rates without any deduction for distributions to shareholders, and such distributions would be taxable as ordinary dividends to the extent of the Fund’s current and accumulated earnings and profits. The current presidential administration has called for significant changes to U.S. fiscal, tax, trade, healthcare, immigration, foreign, and government regulatory policy. In this regard, there is significant uncertainty with respect to legislation, regulation and government policy at the federal level, as well as the state and local levels. Recent events have created a climate of heightened uncertainty and introduced new and difficult-to-quantify macroeconomic and political risks with potentially far-reaching implications. There has been a corresponding meaningful increase in the uncertainty surrounding interest rates, inflation, foreign exchange rates, trade volumes and fiscal and monetary policy. To the extent the U.S. Congress or the current presidential administration implements changes to U.S. policy, those changes may impact, among other things, the U.S. and global economy, international trade and relations, unemployment, immigration, corporate taxes, healthcare, the U.S. regulatory environment, inflation and other areas. Although the Fund cannot predict the impact, if any, of these changes to the Fund’s business, they could adversely affect the Fund’s business, financial condition, operating results and cash flows. Until the Fund knows what policy changes are made and how those changes impact the Fund’s business and the business of the Fund’s competitors over the long term, the Fund will not know if, overall, the Fund will benefit from them or be negatively affected by them. The rules dealing with U.S. federal income taxation are constantly under review by persons involved in the legislative process and by the Internal Revenue Service and the U.S. Treasury Department. Revisions in U.S. federal tax laws and interpretations of these laws could adversely affect the tax consequences of your investment . |  |  |  |  |  |  |  |  |  |
Potential Conflicts of Interest of the Advisor Sub Advisor and Others [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Potential Conflicts of Interest of the Advisor, Sub-Advisor and Others The investment activities of the Advisor, the Sub-Advisor and their affiliates (including BlackRock, Inc. and its subsidiaries (collectively, the “Affiliates”)), and their respective directors, officers or employees, in managing their own accounts and other accounts, may present conflicts of interest that could disadvantage the Fund and its shareholders. The Advisor and its Affiliates may engage in proprietary trading and advise accounts and other funds that have investment objectives similar to those of the Fund and/or that engage in and compete for transactions in the same or similar types of securities, currencies and other assets as are held by the Fund. Subject to the requirements of the Investment Company Act, the Advisor and its Affiliates intend to engage in such activities and may receive compensation from third parties for their services. Neither the Advisor nor any Affiliate is under any obligation to share any investment opportunity, idea or strategy with the Fund. As a result, an Affiliate may compete with the Fund for appropriate investment opportunities. The results of the Fund’s investment activities, therefore, may differ from those of an Affiliate and of other accounts managed by an Affiliate. It is possible that the Fund could sustain losses during periods in which one or more Affiliates and other accounts achieve profits on their trading for proprietary or other accounts. The opposite result is also possible. The Advisor has adopted policies and procedures designed to address potential conflicts of interest. For additional information about potential conflicts of interest and the way in which BlackRock addresses such conflicts, please see “Conflicts of Interest” and “Management of the Fund—Portfolio Management—Potential Material Conflicts of Interest” in the SAI. |  |  |  |  |  |  |  |  |  |
Defensive Investing Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Defensive Investing Risk For defensive purposes, the Fund may allocate assets into cash or short-term fixed-income securities without limitation. In doing so, the Fund may succeed in avoiding losses but may otherwise fail to achieve its investment objective. Further, the value of short-term fixed-income securities may be affected by changing interest rates and by changes in credit ratings of the investments. If the Fund holds cash uninvested it will be subject to the credit risk of the depository institution holding the cash. |  |  |  |  |  |  |  |  |  |
Decision Making Authority Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Decision-Making Authority Risk Investors have no authority to make decisions or to exercise business discretion on behalf of the Fund, except as set forth in the Fund’s governing documents. The authority for all such decisions is generally delegated to the Board, which in turn, has delegated the day-to-day management of the Fund’s investment activities to the Advisors, subject to oversight by the Board. |  |  |  |  |  |  |  |  |  |
Management Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Management Risk The Fund is subject to management risk because it is an actively managed investment portfolio. The Advisors and the individual portfolio managers will apply investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these will produce the desired results. The Fund may be subject to a relatively high level of management risk because the Fund may invest in derivative instruments, which may be highly specialized instruments that require investment techniques and risk analyses different from those associated with equities and bonds. |  |  |  |  |  |  |  |  |  |
Valuation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Valuation Risk The Fund is subject to valuation risk, which is the risk that one or more of the securities in which the Fund invests are valued at prices that the Fund is unable to obtain upon sale due to factors such as incomplete data, market instability or human error. The Advisor may use an independent pricing service or prices provided by dealers to value securities at their market value. Because the secondary markets for certain investments may be limited, such instruments may be difficult to value. See “Net Asset Value.” When market quotations are not available, the Advisor may price such investments pursuant to a number of methodologies, such as computer-based analytical modeling or individual security evaluations. These methodologies generate approximations of market values, and there may be significant professional disagreement about the best methodology for a particular type of financial instrument or different methodologies that might be used under different circumstances. In the absence of an actual market transaction, reliance on such methodologies is essential, but may introduce significant variances in the ultimate valuation of the Fund’s investments. Technological issues and/or errors by pricing services or other third-party service providers may also impact the Fund’s ability to value its investments and the calculation of the Fund’s NAV. When market quotations are not readily available or are believed by the Advisor to be unreliable, the Advisor will fair value the Fund’s investments in accordance with its policies and procedures. Fair value represents a good faith approximation of the value of an asset or liability. The fair value of an asset or liability held by the Fund is the amount the Fund might reasonably expect to receive from the current sale of that asset or the cost to extinguish that liability in an arm’s-length transaction. Fair value pricing may require determinations that are inherently subjective and inexact about the value of a security or other asset. As a result, there can be no assurance that fair value priced assets will not result in future adjustments to the prices of securities or other assets, or that fair value pricing will reflect a price that the Fund is able to obtain upon sale, and it is possible that the fair value determined for a security or other asset will be materially different from quoted or published prices, from the prices used by others for the same security or other asset and/or from the value that actually could be or is realized upon the sale of that security or other asset. For example, the Fund’s NAV could be adversely affected if the Fund’s determinations regarding the fair value of the Fund’s investments were materially higher than the values that the Fund ultimately realizes upon the disposal of such investments. Where market quotations are not readily available, valuation may require more research than for more liquid investments. In addition, elements of judgment may play a greater role in valuation in such cases than for investments with a more active secondary market because there is less reliable objective data available. Because of overall size, duration and maturities of positions held by the Fund, the value at which its investments can be liquidated may differ, sometimes significantly, from the interim valuations obtained by the Fund. In addition, the timing of liquidations may also affect the values obtained on liquidation. Securities held by the Fund may routinely trade with bid-offer spreads that may be significant. There can be no guarantee that the Fund’s investments could ultimately be realized at the Fund’s valuation of such investments. In addition, the Fund’s compliance with the asset diversification tests applicable to regulated investment companies depends on the fair market values of the Fund’s assets, and, accordingly, a challenge to the valuations ascribed by the Fund could affect its ability to comply with those tests or require it to pay penalty taxes in order to cure a violation thereof. The Fund’s NAV per share is a critical component in several operational matters including computation of advisory and services fees and determination of the price at which a tender offer will be made. Consequently, variance in the valuation of the Fund’s investments will impact, positively or negatively, the fees and expenses shareholders will pay. |  |  |  |  |  |  |  |  |  |
Reliance on the Advisor and Sub Advisor Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Reliance on the Advisor and Sub-Advisor Risk The Fund is dependent upon services and resources provided by the Advisors, and therefore the Advisors’ parent, BlackRock, Inc. The Advisors are not required to devote their full time to the business of the Fund and there is no guarantee or requirement that any investment professional or other employee of the Advisors will allocate a substantial portion of his or her time to the Fund. The loss of one or more individuals involved with the Advisors could have a material adverse effect on the performance or the continued operation of the Fund. For additional information on the Advisor, the Sub-Advisor and BlackRock, see “Management of the Fund—Investment Advisor and Sub-Advisor.” |  |  |  |  |  |  |  |  |  |
Reliance on Service Providers Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Reliance on Service Providers Risk The Fund must rely upon the performance of service providers to perform certain functions, which may include functions that are integral to the Fund’s operations and financial performance. Failure by any service provider to carry out its obligations to the Fund in accordance with the terms of its appointment, to exercise due care and skill or to perform its obligations to the Fund at all as a result of insolvency, bankruptcy or other causes could have a material adverse effect on the Fund’s performance and returns to shareholders. The termination of the Fund’s relationship with any service provider, or any delay in appointing a replacement for such service provider, could materially disrupt the business of the Fund and could have a material adverse effect on the Fund’s performance and returns to shareholders. |  |  |  |  |  |  |  |  |  |
Information Technology Systems Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Information Technology Systems Risk The Fund is dependent on the Advisors for certain management services as well as back-office functions. The Advisors depend on information technology systems in order to assess investment opportunities, strategies and markets and to monitor and control risks for the Fund. It is possible that a failure of some kind which causes disruptions to these information technology systems could materially limit the Advisors’ ability to adequately assess and adjust investments, formulate strategies and provide adequate risk control. Any such information technology-related difficulty could harm the performance of the Fund. Further, failure of the back-office functions of the Advisors to process trades in a timely fashion could prejudice the investment performance of the Fund. |  |  |  |  |  |  |  |  |  |
Operational and Technology Risks [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Operational and Technology Risks The Fund and the entities with which it interacts directly or indirectly are susceptible to operational and technology risks, including those related to human errors, processing errors, communication errors, systems failures, cybersecurity incidents, and the use of artificial intelligence and machine learning (“AI”), which may result in losses for the Fund and its shareholders or impair the Fund’s operations. These entities include, but are not limited to, the Fund’s adviser, administrator, distributor, other service providers (e.g., index and benchmark providers, accountants, custodians, and transfer agents), financial intermediaries, counterparties, market makers, authorized participants, listing exchanges, other financial market operators, and governmental authorities. Operational and technology risks for the issuers in which the Fund invests could also result in material adverse consequences for such issuers and may cause the Fund’s investments in such issuers to lose value. The Fund may incur substantial costs in order to mitigate operational and technology risks. Cybersecurity incidents can result from deliberate attacks or unintentional events against an issuer in which the Fund invests, the Fund or any of its service providers. They include, but are not limited to, gaining unauthorized access to systems, misappropriating assets or sensitive information, corrupting or destroying data, and causing operational disruption. Geopolitical tension may increase the scale and sophistication of deliberate attacks, particularly those from nation states or from entities with nation state backing. Cybersecurity incidents may result in any of the following: financial losses; interference with the Fund’s ability to calculate its NAV; disclosure of confidential information; impediments to trading; submission of erroneous trades by the Fund or erroneous subscription or redemption orders; the inability of the Fund or its service providers to transact business; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; and other legal and compliance expenses. Furthermore, cybersecurity incidents may render records of the Fund, including records relating to its assets and transactions, shareholder ownership of Fund shares, and other data integral to the Fund’s functioning, inaccessible, inaccurate or incomplete. Power outages, natural disasters, equipment malfunctions and processing errors that threaten information and technology systems relied upon by the Fund or its service providers, as well as market events that occur at a pace that overloads these systems, may also disrupt business operations or impact critical data. In addition, the risks of increased use of AI technologies, such as machine learning, include data risk, transparency risk, and operational risk. The AI technologies, which are generally highly reliant on the collection and analysis of large amounts of data, may incorporate biased or inaccurate data, and it is not possible or practicable to incorporate all relevant data into such technologies. The output or results of any such AI technologies may therefore be incomplete, erroneous, distorted or misleading. Further, AI tools may lack transparency as to how data is utilized and how outputs are generated. AI technologies may also allow the unintended introduction of vulnerabilities into infrastructures and applications. The Fund and its shareholders could be negatively impacted as a result of these risks associated with AI technologies. AI technologies and their current and potential future applications, and the regulatory frameworks within which they operate, continue to quickly evolve, and it is impossible to anticipate the full scope of future AI capabilities or rules and the associated risks to the Fund. While the Fund’s service providers are required to have appropriate operational, information security and cybersecurity risk management policies and procedures, their methods of risk management may differ from those of the Fund in the setting of priorities, the personnel and resources available or the effectiveness of relevant controls. The Fund and its adviser seek to reduce these risks through controls, procedures and oversight, including establishing business continuity plans and risk management systems. However, there are inherent limitations in such plans and systems, including the possibility that certain risks that may affect the Fund have not been identified or may emerge in the future; that such plans and systems may not completely eliminate the occurrence or mitigate the effects of operational or information security disruptions or failures or of cybersecurity incidents; or that prevention and remediation efforts will not be successful or that incidents will go undetected. The Fund cannot control the systems, information security or other cybersecurity of the issuers in which it invests or its service providers, counterparties, and other third parties whose activities affect the Fund. Lastly, the regulatory climate governing cybersecurity and data protection is developing quickly and may vary considerably across jurisdictions. Regulators continue to develop new rules and standards related to cybersecurity and data protection. Compliance with evolving regulations can be demanding and costly, requiring substantial resources to monitor and implement required changes. |  |  |  |  |  |  |  |  |  |
Misconduct of Employees and of Service Providers Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Misconduct of Employees and of Service Providers Risk Misconduct or misrepresentations by employees of the Advisor, the Sub-Advisor or the Fund’s service providers could cause significant losses to the Fund. Employee misconduct may include binding the Fund to transactions that exceed authorized limits or present unacceptable risks and unauthorized trading activities, concealing unsuccessful trading activities (which, in any case, may result in unknown and unmanaged risks or losses) or making misrepresentations regarding any of the foregoing. Losses could also result from actions by the Fund’s service providers, including, without limitation, failing to recognize trades and misappropriating assets. In addition, employees and service providers may improperly use or disclose confidential information, which could result in litigation or serious financial harm, including limiting the Fund’s business prospects or future marketing activities. Despite the Advisors’ due diligence efforts, misconduct and intentional misrepresentations may be undetected or not fully comprehended, thereby potentially undermining the Advisors’ due diligence efforts. As a result, no assurances can be given that the due diligence performed by the Advisors will identify or prevent any such misconduct. |  |  |  |  |  |  |  |  |  |
Special Risks for Holders of Rights [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Special Risks for Holders of Rights There is a risk that performance of the Fund may result in the common shares purchasable upon exercise of the rights being less attractive to investors at the conclusion of the subscription period. This may reduce or eliminate the value of the rights. Investors who receive rights may find that there is no market to sell rights they do not wish to exercise. If investors exercise only a portion of the rights, common shares may trade at less favorable prices than larger offerings for similar securities. |  |  |  |  |  |  |  |  |  |
Portfolio Turnover Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Portfolio Turnover Risk The Fund’s annual portfolio turnover rate may vary greatly from year to year, as well as within a given year. Portfolio turnover rate is not considered a limiting factor in the execution of investment decisions for the Fund. A higher portfolio turnover rate results in correspondingly greater brokerage commissions and other transactional expenses that are borne by the Fund. High portfolio turnover may result in an increased realization of net short-term capital gains by the Fund which, when distributed to common shareholders, will be taxable as ordinary income. Additionally, in a declining market, portfolio turnover may create realized capital losses. |  |  |  |  |  |  |  |  |  |
Anti Takeover Provisions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Anti-Takeover Provisions Risk The Fund’s Charter and Bylaws include provisions that could limit the ability of other entities or persons to acquire control of the Fund or convert the Fund to open-end status or to change the composition of the Board. Such provisions may limit the ability of shareholders to sell their shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. See “Certain Provisions in the Charter and Bylaws.” |  |  |  |  |  |  |  |  |  |
Investment Limitations [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Investment Limitations The Fund has adopted certain investment limitations designed to limit investment risk. Some of these limitations are fundamental and thus may not be changed without the approval of the holders of a majority of the outstanding common shares. See “Investment Objective and Policies—Investment Restrictions” in the SAI. The restrictions and other limitations set forth throughout this Prospectus and in the SAI apply only at the time of purchase of securities and will not be considered violated unless an excess or deficiency occurs or exists immediately after and as a result of the acquisition of securities. |  |  |  |  |  |  |  |  |  |
Management of Investment Portfolio and Capital Structure to Limit Leverage Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Management of Investment Portfolio and Capital Structure to Limit Leverage Risk The Fund may take certain actions if short-term interest rates increase or market conditions otherwise change (or the Fund anticipates such an increase or change) and any leverage the Fund may have outstanding begins (or is expected) to adversely affect common shareholders. In order to attempt to offset such a negative impact of any outstanding leverage on common shareholders, the Fund may shorten the average maturity of its investment portfolio (by investing in short-term securities) or may reduce any indebtedness that it may have incurred. The success of any such atte mp t to limit leverage risk depends on the Advisors’ ability to accurately predict interest rate or other market changes. Because of the difficulty of making such predictions, the Fund may never attempt to manage its capital structure in the manner described in this paragraph. If market conditions suggest that employing leverage, or employing additional leverage if the Fund already has outstanding leverage, would be beneficial, the Fund may enter into one or more credit facilities, increase any existing credit facilities, sell preferred shares or engage in additional leverage transactions, subject to the restrictions of the Investment Company Act. |  |  |  |  |  |  |  |  |  |
Strategic Transactions [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Strategic Transactions The Fund may use certain Strategic Transactions designed to limit the risk of price fluctuations of securities and to preserve capital. These Strategic Transactions include using swaps, financial futures contracts, options on financial futures or options based on either an index of long-term securities, or on securities whose prices, in the opinion of the Advisors, correlate with the prices of the Fund’s investments. There can be no assurance that Strategic Transactions will be used or used effectively to limit risk, and Strategic Transactions may be subject to their own risks. |  |  |  |  |  |  |  |  |  |
Regulation as a Commodity Pool [Member] |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  | Regulation as a “Commodity Pool” The CFTC subjects advisers to registered investment companies to regulation by the CFTC if a fund that is advised by the investment adviser either (i) invests, directly or indirectly, more than a prescribed level of its liquidation value in CFTC-regulated futures, options and swaps (“CFTC Derivatives”), or (ii) markets itself as providing investment exposure to such instruments. To the extent the Fund uses CFTC Derivatives, it intends to do so below such prescribed levels and will not market itself as a “commodity pool” or a vehicle for trading such instruments. Accordingly, the Advisor has claimed an exclusion from the definition of the term “commodity pool operator” under the Commodity Exchange Act (“CEA”) pursuant to Rule 4.5 under the CEA. The Advisor is not, therefore, subject to registration or regulation as a “commodity pool operator” under the CEA in respect of the Fund. |  |  |  |  |  |  |  |  |  |
Business Contact [Member] |  |  |  |  |  |  |  |  |  |  |  |
Cover [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Entity Address, Address Line One |  | 50 Hudson Yards |  |  |  |  |  |  |  |  |  |
Entity Address, City or Town |  | New York |  |  |  |  |  |  |  |  |  |
Entity Address, State or Province |  | NY |  |  |  |  |  |  |  |  |  |
Entity Address, Postal Zip Code |  | 10001 |  |  |  |  |  |  |  |  |  |
Contact Personnel Name |  | John M. Perlowski, President |  |  |  |  |  |  |  |  |  |
Common Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |
Other Annual Expenses [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Basis of Transaction Fees, Note [Text Block] |  | as a percentage of net assets attributable to common shares |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Lowest Price or Bid |  |  | $ 11.28 | $ 11.32 | $ 11.39 | $ 11.77 | $ 11.12 | $ 11.73 | $ 10.56 | $ 11.15 | $ 12.12 | $ 12.39
Highest Price or Bid |  |  | 11.98 | 11.85 | 12.53 | 12.61 | 11.93 | 12.36 | 12.6 | 12.32 | 12.87 | 13.27
Lowest Price or Bid, NAV |  |  | 11.8 | 11.6 | 11.76 | 11.97 | 11.75 | 12.19 | 11.52 | 11.95 | 12.72 | 12.97
Highest Price or Bid, NAV |  |  | $ 12.13 | $ 11.99 | $ 12.7 | $ 12.82 | $ 12.06 | $ 12.73 | $ 12.81 | $ 12.83 | $ 13.56 | $ 13.73
Highest Price or Bid, Premium (Discount) to NAV [Percent] |  |  | (1.24%) | (1.17%) | (1.34%) | (1.64%) | (1.08%) | (2.95%) | (1.64%) | (3.98%) | (5.09%) | (3.35%)
Lowest Price or Bid, Premium (Discount) to NAV [Percent] |  |  | (4.41%) | (2.41%) | (3.15%) | (1.67%) | (5.36%) | (3.77%) | (8.33%) | (6.69%) | (4.72%) | (4.47%)
Share Price |  | $ 11.83 |  |  |  |  |  |  |  |  |  |
NAV Per Share |  | $ 12.01 |  |  |  |  |  |  |  |  |  |
Latest Premium (Discount) to NAV [Percent] |  | (1.50%) |  |  |  |  |  |  |  |  |  |
Capital Stock, Long-Term Debt, and Other Securities [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Outstanding Security, Title [Text Block] |  | Common Shares |  |  |  |  |  |  |  |  |  |
Outstanding Security, Authorized [Shares] |  | 200,000,000 |  |  |  |  |  |  |  |  |  |
Outstanding Security, Held [Shares] |  | 0 |  |  |  |  |  |  |  |  |  |
Outstanding Security, Not Held [Shares] |  | 24,291,714 |  |  |  |  |  |  |  |  |  |
[1] | If the common shares are sold to or through underwriters, the Prospectus Supplement will set forth any applicable sales load and the estimated offering expenses. Fund shareholders will pay all offering expenses involved with an offering.
[2] | The Reinvestment Plan Agent’s (as defined below under “Dividend Reinvestment Plan”) fees for the handling of the reinvestment of dividends will be paid by the Fund. However, you will pay a $0.02 per share fee incurred in connection with open-market purchases, which will be deducted from the value of the dividend. You will also be charged a $2.50 sales fee and pay a $0.15 per share fee if you direct the Reinvestment Plan Agent to sell your common shares held in a dividend reinvestment account. Per share fees include any applicable brokerage commissions the Reinvestment Plan Agent is required to pay.
[3] | The Fund and the Advisor have entered into a fee waiver agreement (the “Fee Waiver Agreement”), pursuant to which the Advisor has contractually agreed to waive the management fee with respect to any portion of the Fund’s assets attributable to investments in any equity and fixed-income mutual funds and exchange-traded funds (“ETFs”) managed by the Advisor or its affiliates and other exchange-traded products sponsored by the Advisor or its affiliates, in each case that have a contractual management fee, through June 30, 2027. In addition, pursuant to the Fee Waiver Agreement, the Advisor has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to the Advisor indirectly through its investment in money market funds managed by the Advisor or its affiliates, through June 30, 2027. The Fee Waiver Agreement may be terminated at any time, without the payment of any penalty, only by the Fund (upon the vote of a majority of the Directors who are not “interested persons” (as defined in the Investment Company Act) of the Fund (the “Independent Directors”) or a majority of the outstanding voting securities of the Fund), upon 90 days’ written notice by the Fund to the Advisor.
[4] | The Fund currently pays the Advisor a monthly fee at an annual contractual investment management fee rate of 0.65% of the average weekly value of the Fund’s Net Assets. “Net Assets” means the total assets of the Fund minus the sum of its accrued liabilities (including the aggregate indebtedness constituting financial leverage).
[5] | Assumes the use of leverage in the form of reverse repurchase agreements representing 25.6% of Managed Assets at an annual interest expense to the Fund of 5.29% which is based on current market conditions. The actual amount of interest expense borne by the Fund will vary over time in accordance with the level of the Fund’s use of reverse repurchase agreements and variations in market interest rates. Interest expense is required to be treated as an expense of the Fund for accounting purposes.
[6] | “Other Expenses” have been restated to reflect current Acquired Fund Fees and Expenses, which are less than 0.01%.

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