| N-2 - USD ($) | 3 Months Ended | 11 Months Ended | 12 Months Ended | ||||||||||||||||||||||
| Sep. 30, 2023 | Oct. 31, 2022 | Oct. 31, 2021 | Oct. 31, 2020 | Oct. 31, 2019 | Oct. 31, 2018 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2023 | Sep. 30, 2023 | Sep. 30, 2017 | Sep. 30, 2016 | ||||||||
| Prospectus: | |||||||||||||||||||||||||
| Document Period End Date | Sep. 30, 2023 | ||||||||||||||||||||||||
| Cover [Abstract] | |||||||||||||||||||||||||
| Entity Central Index Key | 0000009521 | ||||||||||||||||||||||||
| Amendment Flag | false | ||||||||||||||||||||||||
| Document Type | N-CSR | ||||||||||||||||||||||||
| Entity Registrant Name | Bancroft Fund Ltd. | ||||||||||||||||||||||||
| Fee Table [Abstract] | |||||||||||||||||||||||||
| Shareholder Transaction Expenses [Table Text Block] | Shareholder Transaction Expenses Sales Load ( as a percentage of offering price ) — Offering Expenses Borne by the Fund ( as a percentage of offering price ) — Dividend Reinvestment and Voluntary Cash Purchase Plan Fees Purchase Transactions $ 1.25 | ||||||||||||||||||||||||
| Sales Load [Percent] | [1] | 0% | |||||||||||||||||||||||
| Other Transaction Expenses [Abstract] | |||||||||||||||||||||||||
| Other Transaction Expenses [Percent] | [1] | 0% | |||||||||||||||||||||||
| Annual Expenses [Table Text Block] | Percentages of Net Assets Annual Expenses Attributable to Common Shares Management Fees 0.94% Interest Expense — Other Expenses 0.60% Total Annual Expenses 1.54% Dividends on Preferred Shares 1.50% Total Annual Expenses and Dividends on Preferred 3.04% (a) If common shares are sold to or through underwriters or dealer managers, a prospectus or prospectus supplement will set forth any applicable sales load and the estimated offering expenses borne by the Fund. (b) Shareholders participating in the Fund’s automatic dividend reinvestment plan do not incur any additional fees. Shareholders participating in the voluntary cash purchase plan would pay $1.25 plus their pro rata share of brokerage commissions per transaction to purchase shares and just their pro rata share of brokerage commissions per transaction to sell shares. See “Automatic Dividend Reinvestment and Voluntary Cash Purchase Plan.” (c) The Investment Adviser’s fee is a monthly fee computed at an annual rate of 0.80% of the first $100,000,000 of average weekly net assets and 0.55% of average weekly net assets in excess of $100,000,000 including proceeds attributable to any outstanding preferred shares, with no deduction for the liquidation preference of any preferred shares. Consequently, if the Fund has preferred shares or notes outstanding, all else being equal, the investment management fees and other expenses as a percentage of net assets attributable to common shares will be higher than if the Fund does not utilize a leveraged capital structure. (d) “Other Expenses” are estimated based on the Fund’s fiscal year ended September 30, 2023. (e) Dividends on Preferred Shares represent the estimated annual distributions on the existing preferred shares outstanding. | ||||||||||||||||||||||||
| Management Fees [Percent] | [2] | 0.94% | |||||||||||||||||||||||
| Interest Expenses on Borrowings [Percent] | 0% | ||||||||||||||||||||||||
| Dividend Expenses on Preferred Shares [Percent] | [3] | 1.50% | |||||||||||||||||||||||
| Other Annual Expenses [Abstract] | |||||||||||||||||||||||||
| Other Annual Expenses [Percent] | [4] | 0.60% | |||||||||||||||||||||||
| Total Annual Expenses [Percent] | 1.54% | ||||||||||||||||||||||||
| Net Expense over Assets [Percent] | 3.04% | ||||||||||||||||||||||||
| Expense Example [Table Text Block] | For a more complete description of the various costs and expenses a common shareholder would bear in connection with the issuance and ongoing maintenance of any preferred shares or notes issued by the Fund, see “Risk Factors and Special Considerations—Special Risks to Holders of Common Shares—Leverage Risk.” The following example illustrates the expenses 1 Year 3 Year 5 Year 10 Year Total Expenses Incurred $ 31 $ 94 $ 160 $ 336 * The example should not be considered a representation of future expenses. The example is based on total Annual Expenses and Dividends on Preferred Shares shown in the table above and assumes that the amounts set forth in the table do not change and that all distributions are reinvested at net asset value. Actual expenses may be greater or less than those assumed. Moreover, the Fund’s actual rate of return may be greater or less than the hypothetical 5% return shown in the example. The example includes Dividends on Preferred Shares. If Dividends on Preferred Shares were not included in the example calculation, the expenses for the 1-, 3-, 5- and 10-year periods in the table above would be as follows (based on the same assumptions as above): $16, $49, $84, and $183. | ||||||||||||||||||||||||
| Expense Example, Year 01 | $ 31 | ||||||||||||||||||||||||
| Expense Example, Years 1 to 3 | 94 | ||||||||||||||||||||||||
| Expense Example, Years 1 to 5 | 160 | ||||||||||||||||||||||||
| Expense Example, Years 1 to 10 | $ 336 | ||||||||||||||||||||||||
| Purpose of Fee Table , Note [Text Block] | The following table shows the Fund’s expenses | ||||||||||||||||||||||||
| Basis of Transaction Fees, Note [Text Block] | as a percentage of offering price | ||||||||||||||||||||||||
| Other Transaction Fees, Note [Text Block] | If common shares are sold to or through underwriters or dealer managers, a prospectus or prospectus supplement will set forth any applicable sales load and the estimated offering expenses borne by the Fund. | ||||||||||||||||||||||||
| Other Expenses, Note [Text Block] | “Other Expenses” are estimated based on the Fund’s fiscal year ended September 30, 2023. | ||||||||||||||||||||||||
| Financial Highlights [Abstract] | |||||||||||||||||||||||||
| Senior Securities Averaging Method, Note [Text Block] | Based on weekly prices. | ||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Investment Objectives and Practices [Text Block] | INVESTMENT OBJECTIVES AND POLICIES Investment Objectives The investment objective of the Fund is to provide income and the potential for capital appreciation by investing primarily in convertible securities. Under normal market conditions, the Fund invests at least 65% of its assets Bancroft Fund Ltd. Additional Fund Information (Continued) (Unaudited) (consisting of net assets plus the amount of any borrowing for investment purposes) in convertible securities. There can be no assurance that the Fund will achieve its investment objectives. Investment Policies The Fund expects that a substantial majority of its assets will consist of convertible securities. The Fund has adopted a non-fundamental investment policy providing that the Fund will invest, under normal market conditions, at least 65% of the value of its assets (consisting of net assets plus the amount of any borrowings for investment purposes) in convertible securities. Convertible securities include debt securities and preferred stocks which are convertible into, or carry the right to purchase, common stock or other equity securities. The debt security or preferred stock may itself be convertible into or exchangeable for equity securities, or the conversion privilege may be evidenced by warrants attached to the security or acquired as part of a unit with the security. A convertible security may also be structured so that it is convertible at the option of the holder or the issuer, or subject to mandatory conversion. The Fund may invest in convertible securities rated in the lower rating categories of the established rating services (“Ba” or lower by Moody’s or “BB” or lower by S&P) or unrated debt instruments which are in the judgment of the Fund’s Investment Adviser of equivalent quality. Debt securities rated below investment grade commonly are referred to as “junk bonds.” The average duration of the Fund’s investments in debt securities is expected to vary and the Fund does not target any particular average duration. Under normal market conditions, the remaining 35% or less of the Fund’s assets may be invested in other securities, including common stocks, non-convertible preferred stocks and investment grade debt securities, common stock received upon conversion or exchange of securities, options, warrants, securities of the U.S. government, its agencies and instrumentalities, foreign securities, American Depositary Receipts or repurchase agreements, or they may be held as cash or cash equivalents. The Fund does not intend to participate in derivative transactions other than options transactions as described herein. See “—Other Investment Practices—Options.” The Fund is not required to sell securities for the purpose of assuring that 65% of its assets are invested in convertible securities. No assurances can be given that the Fund’s objective will be achieved. Neither the Fund’s investment objective nor, except as expressly listed under “Investment Restrictions” in the SAI, any of its policies are fundamental, and each may be modified by the Board without shareholder approval. The percentage and ratings limitations stated herein and in the SAI apply only at the time of investment and are not considered violated as a result of subsequent changes to the value, or downgrades to the ratings, of the Fund’s portfolio investments. Principal Investment Practices and Policies Convertible Securities such risk is reduced depends in large measure upon the degree to which the convertible security sells above its value as a fixed income security. The Fund is also permitted to invest in certain other securities with innovative structures in the convertible securities market. These include “mandatory conversion” securities, which consist of debt securities or preferred stocks that convert automatically into common stock of the same or a different issuer at a specified date and conversion ratio. The market value of a convertible security may be viewed as comprised of two components: its “investment value,” which is its value based on its yield without regard to its conversion feature; and its “conversion value,” which is its value attributable to the underlying common stock obtainable on conversion. The investment value of a convertible security is influenced by changes in interest rates and the yield of similar non-convertible securities, with investment value declining as interest rates increase and increasing as interest rates decrease. The conversion value of a convertible security is influenced by changes in the market price of the underlying common stock. If, because of a low price of the underlying common stock, the conversion value is low relative to the investment value, the price of the convertible security is governed principally by its investment value. To the extent the market price of the underlying common stock approaches or exceeds the conversion price, the convertible security will be increasingly influenced by its conversion value and the convertible security may sell at a premium over its conversion value to the extent investors place value on the right to acquire the underlying common stock while holding a fixed income security. Accordingly, convertible securities have unique investment characteristics because (i) they have relatively high yields as compared to common stocks, (ii) they have defensive characteristics since they provide a fixed return even if the market price of the underlying common stock declines, and (iii) they provide the potential for capital appreciation if the market price of the underlying common stock increases. A convertible security may be subject to redemption at the option of the issuer at a price established in the charter provision or indenture pursuant to which the convertible security is issued. If a convertible security held by the Fund is called for redemption, the Fund will be required to surrender the security for redemption, convert it into the underlying common stock or sell it to a third party. Before the Fund purchases a convertible security it will review carefully the redemption provisions of the security. There may be additional types of convertible securities with features not specifically referred to herein in which the Fund may invest consistent with its investment objectives and policies. For a discussion of risk factors of convertible securities, see “Risk Factors and Special Considerations—Convertible Securities Risk.” Synthetic Convertible Securities. options on a stock index. Unlike a traditional convertible security, which is a single security having a single market value, a synthetic convertible comprises two or more separate securities, each with its own market value. Because the “market value” of a synthetic convertible security is the sum of the values of its income-producing component and its convertible component, the value of a synthetic convertible security may respond differently to market fluctuations than a traditional convertible security. The Fund also may purchase synthetic convertible securities created by other parties, including convertible structured notes. Convertible structured notes are income-producing debentures linked to equity. Convertible structured notes have the attributes of a convertible security; however, the issuer of the convertible note (typically an investment bank), rather than the issuer of the underlying common stock into which the note is convertible, assumes credit risk associated with the underlying investment and the Fund in turn assumes credit risk associated with the issuer of the convertible note. Equity Securities. Common stocks represent the residual ownership interest in the issuer and holders of common stock are entitled to the income and increase in the value of the assets and business of the issuer after all of its debt obligations and obligations to preferred shareholders are satisfied. Common stocks generally have voting rights. Common stocks fluctuate in price in response to many factors including historical and prospective earnings of the issuer, the value of its assets, general economic conditions, interest rates, investor perceptions and market liquidity. Equity securities also include preferred stock (whether or not convertible into common stock) and debt securities convertible into or exchangeable for common or preferred stock. Preferred stock has a preference over common stock in liquidation (and generally dividends as well) but is subordinated to the liabilities of the issuer in all respects. As a general rule the market value of preferred stock with a fixed dividend rate and no conversion element varies inversely with interest rates and perceived credit risk, while the market price of convertible preferred stock generally also reflects some element of conversion value. Because preferred stock is junior to debt securities and other obligations of the issuer, deterioration in the credit quality of the issuer will cause greater changes in the value of a preferred stock than in a more senior debt security with similarly stated yield characteristics. The market value of preferred stock will also generally reflect whether (and if so when) the issuer may force holders to sell their preferred stock back to the issuer and whether (and if so when) the holders may force the issuer to buy back their preferred stock. Generally speaking, the right of the issuer to repurchase the preferred stock tends to reduce any premium at which the preferred stock might otherwise trade due to interest rate or credit factors, while the right of the holders to require the issuer to repurchase the preferred stock tends to reduce any discount at which the preferred stock might otherwise trade due to interest rate or credit factors. In addition, some preferred stocks are non-cumulative, meaning that the dividends do not accumulate and need not ever be paid. A portion of the portfolio may include investments in non-cumulative preferred stocks, whereby the issuer does not have an obligation to make up any arrearages to its shareholders. There is no assurance that dividends or distributions on non-cumulative preferred stocks in which the Fund invests will be declared or otherwise made payable. Income Securities. holder of the security a specified return, which may be either fixed or reset periodically in accordance with the terms of the security. Fixed income securities generally are senior to an issuer’s common stock and their holders generally are entitled to receive amounts due before any distributions are made to common shareholders. Common stocks, on the other hand, generally do not obligate an issuer to make periodic distributions to holders. The market value of fixed income securities, especially those that provide a fixed rate of return, may be expected to rise and fall inversely with interest rates and in general is affected by the credit rating of the issuer, the issuer’s performance and perceptions of the issuer in the market place. The market value of callable or redeemable fixed income securities may also be affected by the issuer’s call and redemption rights. In addition, it is possible that the issuer of fixed income securities may not be able to meet its interest or principal obligations to holders. Further, holders of non-convertible fixed income securities do not participate in any capital appreciation of the issuer. The Fund may also invest in obligations of government sponsored instrumentalities. Unlike non-U.S. government securities, obligations of certain agencies and instrumentalities of the U.S. government, such as the Government National Mortgage Association, are supported by the “full faith and credit” of the U.S. government; others, such as those of the Export-Import Bank of the U.S., are supported by the right of the issuer to borrow from the U.S. Treasury; others, such as those of the Federal National Mortgage Association, are supported by the discretionary authority of the U.S. government to purchase the agency’s obligations; and still others, such as those of the Student Loan Marketing Association, are supported only by the credit of the instrumentality. No assurance can be given that the U.S. government would provide financial support to U.S. government sponsored instrumentalities if it is not obligated to do so by law. The Fund also may invest in common stock of issuers that have historically paid periodic dividends or otherwise made distributions to common shareholders. Unlike fixed income securities, dividend payments generally are not guaranteed and so may be discontinued by the issuer at its discretion or because of the issuer’s inability to satisfy its liabilities. Further, an issuer’s history of paying dividends does not guarantee that it will continue to pay dividends in the future. In addition to dividends, under certain circumstances the holders of common stock may benefit from the capital appreciation of the issuer. Common stocks represent the residual ownership interest in the issuer and holders of common stock are entitled to the income and increase in the value of the assets and business of the issuer after all of its debt obligations and obligations to preferred shareholders are satisfied. Common stocks generally have voting rights. Common stocks fluctuate in price in response to many factors including historical and prospective earnings of the issuer, the value of its assets, general economic conditions, interest rates, investor perceptions and market liquidity. Non-Investment Grade Securities. Generally, such non-investment grade securities and unrated securities of comparable quality offer a higher current yield than is offered by higher rated securities, but also (i) will likely have some quality and protective characteristics that, in the judgment of the rating organizations, are outweighed by large uncertainties or major risk exposures to adverse conditions, and (ii) are predominantly speculative with respect to the issuer’s capacity to pay interest and repay principal in accordance with the terms of the obligation. The market values of certain of these securities also tend to be more sensitive to individual corporate developments and changes in economic conditions than higher quality securities. In addition, such comparable unrated securities generally present a higher degree of credit risk. The risk of loss due to default by these issuers is significantly greater because such non-investment grade securities and unrated securities of comparable quality generally are unsecured and frequently are subordinated to the prior payment of senior indebtedness. In light of these risks, the Investment Adviser, in evaluating the creditworthiness of an issue, whether rated or unrated, will take various factors into consideration, which may include, as applicable, the issuer’s operating history, financial resources and its sensitivity to economic conditions and trends, the market support for the facility financed by the issue, the perceived ability and integrity of the issuer’s management and regulatory matters. In addition, the market value of non-investment grade securities is more volatile than that of higher quality securities, and the markets in which such lower rated or unrated securities are traded are more limited than those in which higher rated securities are traded. The existence of limited markets may make it more difficult for the Fund to obtain accurate market quotations for purposes of valuing its portfolio and calculating its net asset value. Moreover, the lack of a liquid trading market may restrict the availability of securities for the Fund to purchase and may also have the effect of limiting the ability of the Fund to sell securities at their fair value in order to respond to changes in the economy or the financial markets. Non-investment grade securities and unrated securities of comparable quality also present risks based on payment expectations. If an issuer calls the obligation for redemption (often a feature of fixed-income securities), the Fund may have to replace the security with a lower yielding security, resulting in a decreased return for investors. Also, as the principal value of non-convertible bonds and preferred stocks moves inversely with movements in interest rates, in the event of rising interest rates the value of the securities held by the Fund may decline proportionately more than a portfolio consisting of higher rated securities. Investments in zero coupon bonds may be more speculative and subject to greater fluctuations in value due to changes in interest rates than bonds that pay interest currently. Interest rates are at historical lows and, therefore, it is likely that they will rise in the future. As part of its investments in non-investment grade securities, the Fund may invest in securities of issuers in default. The Fund will make an investment in securities of issuers in default only when the Investment Adviser believes that such issuers will honor their obligations or emerge from bankruptcy protection and the value of these securities will appreciate. By investing in securities of issuers in default, the Fund bears the risk that these issuers will not continue to honor their obligations or emerge from bankruptcy protection or that the value of the securities will not otherwise appreciate. In addition to using recognized rating agencies and other sources, the Investment Adviser also performs its own analysis of issues in seeking investments that it believes to be underrated (and thus higher yielding) in light of the financial condition of the issuer. Its analysis of issuers may include, among other things, current and anticipated cash flow and borrowing requirements, value of assets in relation to historical cost, strength of management, responsiveness to business conditions, credit standing and current anticipated results of operations. In selecting investments for the Fund, the Investment Adviser may also consider general business conditions, anticipated changes in interest rates and the outlook for specific industries. Subsequent to its purchase by the Fund, an issue of securities may cease to be rated or its rating may be reduced. In addition, it is possible that statistical rating agencies might change their ratings of a particular issue to reflect subsequent events on a timely basis. Moreover, such ratings do not assess the risk of a decline in market value. None of these events will require the sale of the securities by the Fund, although the Investment Adviser will consider these events in determining whether the Fund should continue to hold the securities. The market for non-investment grade and comparable unrated securities has experienced periods of significantly adverse price and liquidity several times, particularly at or around times of economic recession. Past market recessions have adversely affected the value of such securities and the ability of certain issuers of such securities to repay principal and pay interest thereon or to refinance such securities. The market for those securities may react in a similar fashion in the future. Investment Grade Securities. Leverage. The use of leverage magnifies the impact of changes in net asset value, which means that, all else being equal, the use of leverage results in outperformance on the upside and underperformance on the downside. In addition, if the cost of leverage exceeds the return on the securities acquired with the proceeds of leverage, the use of leverage will diminish rather than enhance the return to the Fund. The use of leverage generally increases the volatility of returns to the Fund. Such volatility may increase the likelihood of the Fund having to sell investments in order to meet its obligations to make distributions on the preferred shares or principal or interest payments on debt securities, or to redeem preferred shares or repay debt, when it may be disadvantageous to do so. The Fund’s use of leverage may require it to sell portfolio investments at inopportune times in order to raise cash to redeem preferred shares or otherwise de-leverage so as to maintain required asset coverage amounts or comply with any mandatory redemption terms of any outstanding preferred shares. See “—Risk Factors and Special Considerations—Special Risks to Holders of Common Shares—Leverage Risk.” In the event the Fund had both outstanding preferred shares and senior securities representing debt at the same time, the Fund’s obligations to pay dividends or distributions and, upon liquidation of the Fund, liquidation payments in respect of its preferred shares would be subordinate to the Fund’s obligations to make any principal and/or interest payments due and owing with respect to its outstanding senior debt securities. Accordingly, the Fund’s issuance of senior securities representing debt would have the effect of creating special risks for the Fund’s preferred shareholders that would not be present in a capital structure that did not include such securities. Subject to the requirements of Rule 18f-4 under the 1940 Act, the Fund may enter into derivative transactions including transactions that have economic leverage embedded in them. Rule 18f-4 defines “derivatives transactions” as (1) any swap, security-based swap, futures contract, forward contract, option, any combination of the foregoing, or any similar instrument, under which a fund is or may be required to make any payment or delivery of cash or other assets during the life of the instrument or at maturity or early termination, whether as margin or settlement payment or otherwise; and (2) any short sale borrowing. Derivatives transactions entered into by the Fund in compliance with Rule 18f-4 will not be considered senior securities for purposes of computing the asset coverage requirements described above. Economic leverage exists when the Fund achieves the right to a return on a capital base that exceeds the investment which the Fund has contributed to the instrument achieving a return. Derivative transactions that the Fund may enter into and the risks associated with them are described elsewhere in this Annual Report. The Fund cannot assure you that investments in derivative transactions that have economic leverage embedded in them will result in a higher return on its common shares. If the Fund enters into any reverse repurchase agreement or similar financing transactions obligating the Fund to make future payments, the Fund must either treat all such transactions as derivatives transactions for all purposes under Rule 18f-4 or otherwise comply with the asset coverage requirements described above and combine the aggregate amount of indebtedness associated with all such transactions with the aggregate amount of any other senior securities representing indebtedness when calculating the Fund’s asset coverage ratio limit requirements. The asset coverage requirements under section 18 of the 1940 Act and the limits and conditions imposed by Rule 18f-4 may limit or restrict portfolio management. Foreign Securities American Depositary Receipts. about foreign companies than is available about domestic companies. Foreign companies are not subject to uniform accounting, auditing and financial reporting standards, practices and requirements comparable to those applicable to domestic companies. Emerging Market Countries. Restricted and Illiquid Securities. It may be difficult to sell such securities at a price representing the fair value until such time as such securities may be sold publicly. Where registration is required, a considerable period may elapse between a decision to sell the securities and the time when it would be permitted to sell. Thus, the Fund may not be able to obtain as favorable a price as that prevailing at the time of the decision to sell. The Fund may also acquire securities through private placements under which it may agree to contractual restrictions on the resale of such securities. Such restrictions might prevent their sale at a time when such sale would otherwise be desirable. Other Investment Practices U.S. Government Obligations of the U.S. government. Some U.S. government securities, such as U.S. Treasury bills, Treasury notes and Treasury bonds, which differ only in their interest rates, maturities and times of issuance, are supported by the full faith and credit of the United States. Others are supported only by: (i) the right of the issuer to borrow from the U.S. Treasury, such as securities of the Federal Home Loan Banks; (ii) the discretionary authority of the U.S. government to purchase the agency’s obligations, such as securities of the Federal National Mortgage Association; or (iii) only the credit of the issuer. No assurance can be given that the U.S. government will provide financial support in the future to U.S. government agencies, authorities or instrumentalities that are not supported by the full faith and credit of the United States. Securities guaranteed as to principal and interest by the U.S. government, its agencies, authorities or instrumentalities include: (i) securities for which the payment of principal and interest is backed by an irrevocable letter of credit issued by the U.S. government or any of its agencies, authorities or instrumentalities; and (ii) participations in loans made to non-U.S. governments or other entities that are so guaranteed. The secondary market for certain of these participations is limited and, therefore, may be regarded as illiquid. Short Sales. The Fund will normally close out a short position by purchasing and delivering an equal amount of the securities sold short, rather than by delivering securities already held by the Fund. The Fund may, however, close out any short sale of common stock through the conversion or exchange of securities or the exercise of warrants or rights it owns, or through the delivery of common stock already held by the Fund. The Fund may make a short sale in order to hedge against market risks when it believes that the price of a security may decline, causing a decline in the value of a long position the Fund may have in such security or a security convertible into or exchangeable for such security, or when, for tax or other reasons, the Fund does not want to sell the security it owns. In such case, any future losses in the Fund’s long position should be reduced by a gain in the short position. Conversely, any gain in the long position should be reduced by a loss in the short position. 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, U.S. government securities or other highly liquid debt 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. The extent to which such gains or losses are reduced will depend upon the amount of the security sold short relative to the amount the Fund owns, either directly or indirectly, and, in the case where the Fund owns convertible securities, changes with the conversion premiums. Warrants. never exceed the exercise price before the expiration date of the warrant, the purchaser of the warrant risks the loss of the entire purchase price of the warrant. Warrants generally trade in the open market and may be sold rather than exercised. Warrants are sometimes sold in unit form with other securities of an issuer. Units of warrants and common stock may be employed in financing young, unseasoned companies. The purchase price of a warrant varies with the exercise price of the warrant, the current market value of the underlying security, the life of the warrant and various other investment factors. Lending of Portfolio Securities. Repurchase Agreements Temporary Defensive Investments. of the Federal Deposit Insurance Corporation. During temporary defensive periods, the Fund may also invest to the extent permitted by applicable law in shares of money market mutual funds. Money market mutual funds are investment companies and the investments in those companies by the Fund are in some cases subject to certain fundamental investment restrictions and applicable law. As a shareholder in a mutual fund, the Fund will bear its ratable share of its expenses, including management fees, and will remain subject to payment of the fees to the Investment Adviser, with respect to assets so invested. The Fund may find it more difficult to achieve its investment objective during temporary defensive periods. Options. A call option is a contract that gives the holder of the option the right to buy from the writer of the call option, in return for a premium, the security underlying the option at a specified exercise price at any time during the term of the option. The writer of the call option has the obligation, upon exercise of the option, to deliver the underlying security upon payment of the exercise price during the option period. A call option is “covered” if the Fund owns the underlying instrument covered by the call or has an absolute and immediate right to acquire that instrument without additional cash consideration (or for additional cash consideration held in a segregated account by its custodian) upon conversion or exchange of other instruments held in its portfolio. A call option is also covered if the Fund holds a call on the same instrument as the call written where the exercise price of the call held is (i) equal to or less than the exercise price of the call written or (ii) greater than the exercise price of the call written if the difference is maintained by the Fund in cash, U.S. government securities or other high-grade short-term obligations in a segregated account with its custodian. A put option is “covered” if the Fund maintains cash or other high-grade short-term obligations with a value equal to the exercise price in a segregated account with its custodian, or else holds a put on the same instrument as the put written where the exercise price of the put held is equal to or greater than the exercise price of the put written. A put option is a contract that gives the holder of the option the right, in return for a premium, to sell to the seller the underlying security at a specified price. The seller of the put option has the obligation to buy the underlying security upon exercise at the exercise price. The Fund will write covered call options in order to receive additional income in the form of premiums which it is paid for writing options, and for hedging purposes in order to protect against possible declines in the market values of the stocks or convertible securities held in its portfolio. If the Fund has written an option, it may terminate its obligation by effecting a closing purchase transaction. This is accomplished by purchasing an option of the same series as the option previously written. However, once the Fund has been assigned an exercise notice, the Fund will be unable to effect a closing purchase transaction. Similarly, if the Fund is the holder of an option it may liquidate its position by effecting a closing sale transaction. This is accomplished by selling an option of the same series as the option previously purchased. There can be no assurance that either a closing purchase or sale transaction can be effected when the Fund so desires. The Fund realizes a profit from a closing transaction if the price of the transaction is less than the premium received from writing the option or is more than the premium paid to purchase the option; the Fund realizes a loss from a closing transaction if the price of the transaction is more than the premium received from writing the option or is less than the premium paid to purchase the option. Since call option prices generally reflect increases in the price of the underlying security, any loss resulting from the repurchase of a call option may also be wholly or partially offset by unrealized appreciation of the underlying security. Other principal factors affecting the market value of a put or a call option include supply and demand, interest rates, the current market price and price volatility of the underlying security and the time remaining until the expiration date. Gains and losses on investments in options depend, in part, on the ability of the Investment Adviser to predict correctly the effect of these factors. The use of options cannot serve as a complete hedge since the price movement of securities underlying the options will not necessarily follow the price movements of the portfolio securities subject to the h | ||||||||||||||||||||||||
| Risk Factors [Table Text Block] | RISK FACTORS AND SPECIAL CONSIDERATIONS Investors should consider the following risk factors and special considerations associated with investing in the Fund: General Risks Market Risk. industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors which affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Fund. Even when markets perform well, there is no assurance that the investments held by the Fund will increase in value along with the broader market. In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Fund to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown, which could have an adverse impact on the Fund’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including, but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Fund’s investments. Any market disruptions could also prevent the Fund from executing advantageous investment decisions in a timely manner. To the extent that the Fund focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Fund meets their individual financial needs and tolerance for risk. Current market conditions may pose heightened risks with respect to the Fund’s investment in fixed income securities. Interest rates have risen in recent months, and the risk that they may continue to do so is pronounced. Any interest rate increases in the future could cause the value of the Fund to decrease. Recently, inflation levels have been at their highest point in nearly 40 years and the Federal Reserve has been engaged in an aggressive campaign to raise certain benchmark interest rates in an effort to combat inflation. As inflation increases, the real value of the Fund’s common stock and distributions therefore may decline. Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Fund being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. Convertible Securities Risk The value of a convertible security is influenced by the value of the underlying equity security. Convertible debt securities and preferred stocks may depreciate in value if the market value of the underlying equity security declines or if rates of interest increase. In addition, although debt securities are liabilities of a corporation which the corporation is generally obligated to repay at a specified time, debt securities, particularly convertible debt securities, are often subordinated to the claims of some or all of the other creditors of the corporation. Mandatory conversion securities (securities that automatically convert into equity securities at a future date) may limit the potential for capital appreciation and, in some instances, are subject to complete loss of invested capital. Other innovative convertibles include “equity-linked” securities, which are securities or derivatives that may have fixed, variable or no interest payments prior to maturity, may convert (at the option of the holder or on a mandatory basis) into cash or a combination of cash and common stock, and may be structured to limit the potential for capital appreciation. Equity-linked securities may be illiquid and difficult to value and may be subject to greater credit risk than that of other convertibles. Moreover, mandatory conversion securities and equity-linked securities have increased the sensitivity of the convertible securities market to the volatility of the equity markets and to the special risks of those innovations, which may include risks different from, and possibly greater than, those associated with traditional convertible securities. Preferred stocks are equity securities in the sense that they do not represent a liability of the corporation. In the event of liquidation of the corporation, and after its creditors have been paid or provided for, holders of preferred stock are generally entitled to a preference as to the assets of the corporation before any distribution may be made to the holders of common stock. Debt securities normally do not have voting rights. Preferred stocks may have no voting rights or may have voting rights only under certain circumstances. ● Credit Risk. ● Market Risk. mandatory convertible securities include features which render them more sensitive to price changes of their underlying securities. Thus they expose the Fund to greater downside risk than traditional convertible securities, but generally less than that of the underlying common stock. ● Interest Rate Risk for Convertible Securities. ● Sector Risk. ● Dilution Risk Synthetic Convertible Instruments Risk Equity Risk Common Stock Risk structurally subordinated as to income and residual value to preferred stock, bonds and other debt instruments in a company’s capital structure, in terms of priority to corporate income, and therefore will be subject to greater dividend risk than preferred stock or debt instruments of such issuers. In addition, while common stock has historically generated higher average returns than fixed income securities, common stock has also experienced significantly more volatility in those returns. Preferred Stock Risk ● Deferral. ● Non-Cumulative Dividends. ● Subordination. ● Liquidity. ● Limited Voting Rights. ● Special Redemption Rights. Warrants and Rights Investing in rights and warrants can provide a greater potential for profit or loss than an equivalent investment in the underlying security, and thus can be a riskier investment. The value of a right or warrant may decline because of a decline in the value of the underlying security, the passage of time, changes in interest rates or in the dividend or other policies of the Fund whose equity underlies the warrant, a change in the perception as to the future price of the underlying security, or any combination thereof. Rights and warrants generally pay no dividends and confer no voting or other rights other than the right to purchase the underlying security. Fixed Income Securities Risks ● Interest Rate Risk. ● Issuer Risk. ● Credit Risk. ● Prepayment Risk. ● Reinvestment Risk. ● Duration and Maturity Risk. Specifically, duration measures the anticipated percentage change in NAV that is expected for every percentage point change in interest rates. The two have an inverse relationship. Duration can be a useful tool to estimate anticipated price changes to a fixed pool of income securities associated with changes in interest rates. For example, a duration of five years means that a 1% decrease in interest rates will increase the NAV of the portfolio by approximately 5%; if interest rates increase by 1%, the NAV will decrease by 5%. However, in a managed portfolio of fixed income securities having differing interest or dividend rates or payment schedules, maturities, redemption provisions, call or prepayment provisions and credit qualities, actual price changes in response to changes in interest rates may differ significantly from a duration-based estimate at any given time. Actual price movements experienced by a portfolio of fixed income securities will be affected by how interest rates move (i.e., changes in the relationship of long-term interest rates to short-term interest rates), the magnitude of any move in interest rates, actual and anticipated prepayments of principal through call or redemption features, the extension of maturities through restructuring, the sale of securities for portfolio management purposes, the reinvestment of proceeds from prepayments on and from sales of securities, and credit quality-related considerations whether associated with financing costs to lower credit quality borrowers or otherwise, as well as other factors. Accordingly, while duration maybe a useful tool to estimate potential price movements in relation to changes in interest rates, investors are cautioned that duration alone will not predict actual changes in the net asset or market value of the Fund’s shares and that actual price movements in the Fund’s portfolio may differ significantly from duration-based estimates. Duration differs from maturity in that it takes into account a security’s yield, coupon payments and its principal payments in addition to the amount of time until the security matures. As the value of a security changes over time, so will its duration. Prices of securities with longer durations tend to be more sensitive to interest rate changes than securities with shorter durations. In general, a portfolio of securities with a longer duration can be expected to be more sensitive to interest rate changes than a portfolio with a shorter duration. Any decisions as to the targeted duration or maturity of any particular category of investments will be made based on all pertinent market factors at any given time. The Fund may incur costs in seeking to adjust the portfolio average duration or maturity. There can be no assurance that the Investment Adviser’s assessment of current and projected market conditions will be correct or that any strategy to adjust duration or maturity will be successful at any given time. LIBOR Risk In July 2017, the head of the United Kingdom Financial Conduct Authority announced the desire to phase out the use of LIBOR by the end of 2021. LIBOR can no longer be used to calculate new deals as of December 31, 2021. Since December 31, 2021, all sterling, euro, Swiss franc and Japanese yen LIBOR settings and the 1-week and 2-month U.S. dollar LIBOR settings have ceased to be published or are no longer representative. Overnight and 12-month US dollar LIBOR settings permanently ceased as of June 30, 2023. 1-, 3-, and 6-month U.S. dollar LIBOR settings will continue to be published using a synthetic methodology until September 2024. Various financial industry groups have begun planning for the transition away from LIBOR, but there are challenges to converting certain securities and transactions to a new reference rate. Neither the effect of the LIBOR transition process nor its ultimate success can yet be known. As an alternative to LIBOR, the Financial Reporting Council, in conjunction with the Alternative Reference Rates Committee, a steering committee comprised of large U.S. financial institutions, recommended replacing U.S. dollar LIBOR with the Secured Overnight Financing Rate (“SOFR”), a new index calculated by reference to short-term repurchase agreements, backed by Treasury securities. Abandonment of, or modifications to, LIBOR could have adverse impacts on newly issued financial instruments and any of our existing financial instruments which reference LIBOR. Given the inherent differences between LIBOR and SOFR, or any other alternative benchmark rate that may be established, there are many uncertainties regarding a transition from LIBOR, including, but not limited to, the need to amend all contracts with LIBOR as the referenced rate and how this will impact the cost of variable rate debt and certain derivative financial instruments. In addition, SOFR or other replacement rates may fail to gain market acceptance. Any failure of SOFR or alternative reference rates to gain market acceptance could adversely affect the return on, value of and market for securities linked to such rates. Neither the effect of the LIBOR transition process nor its ultimate success can yet be known. The transition process might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of, new hedges placed against instruments whose terms currently include LIBOR. 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. Moreover, these alternative rate-setting provisions may not be designed for regular use in an environment where LIBOR ceases to be published, and may be an ineffective fallback following the discontinuation of LIBOR. On March 15, 2022, President Biden signed into law the Consolidated Appropriations Act of 2022, which among other things, provides for the use of interest rates based on SOFR in certain contracts currently based on LIBOR and a safe harbor from liability for utilizing SOFR-based interest rates as a replacement for LIBOR. The elimination of LIBOR could have an adverse impact on the market value of and/or transferability of any LIBOR-linked securities, loans, and other financial obligations or extensions of credit held by or due to us or on our overall financial condition or results of operations. Interest Rate Risk Generally The magnitude of these fluctuations in the market price of bonds and other income- or dividend-paying securities is generally greater for those securities with longer maturities. Fluctuations in the market price of the Fund’s investments will not affect interest income derived from instruments already owned by the Fund, but will be reflected in the Fund’s net asset value. The Fund may lose money if short-term or long-term interest rates rise sharply in a manner not anticipated by Fund management. To the extent the Fund invests in debt securities that may be prepaid at the option of the obligor, the sensitivity of such securities to changes in interest rates may increase (to the detriment of the Fund) when interest rates rise. Moreover, because rates on certain floating rate debt securities typically reset only periodically, changes in prevailing interest rates (and particularly sudden and significant changes) can be expected to cause some fluctuations in the net asset value of the Fund to the extent that it invests in floating rate debt securities. These basic principles of bond prices also apply to U.S. government securities. A security backed by the “full faith and credit” of the U.S. government is guaranteed only as to its stated interest rate and face value at maturity, not its current market price. Just like other income- or dividend-paying securities, government-guaranteed securities will fluctuate in value when interest rates change. The Fund’s use of leverage will tend to increase the Fund’s interest rate risk. The Fund may invest in variable and floating rate debt instruments, which generally are less sensitive to interest rate changes than longer duration fixed rate instruments, but may decline in value in response to rising interest rates if, for example, the rates at which they pay interest do not rise as much, or as quickly, as market interest rates in general. Conversely, variable and floating rate instruments generally will not increase in value if interest rates decline. The Fund also may invest in inverse floating rate debt securities, which may decrease in value if interest rates increase, and which also may exhibit greater price volatility than fixed rate debt obligations with similar credit quality. To the extent the Fund holds variable or floating rate instruments, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities, which may adversely affect the net asset value of the Fund’s common shares. Corporate Bonds Risk Non-Investment Grade Securities government securities or securities of investment grade issuers because they are subject to greater risks than these securities. These risks, which reflect their speculative character, include the following: ● greater volatility; ● greater credit risk and risk of default; ● potentially greater sensitivity to general economic or industry conditions; ● potential lack of attractive resale opportunities (illiquidity); and ● additional expenses to seek recovery from issuers who default. In addition, the prices of these non-investment grade securities are more sensitive to negative developments, such as a decline in the issuer’s revenues or a general economic downturn, than are the prices of higher grade securities. Non-investment grade securities tend to be less liquid than investment grade securities. The market value of non-investment grade securities may be more volatile than the market value of investment grade securities and generally tends to reflect the market’s perception of the creditworthiness of the issuer and short-term market developments to a greater extent than investment grade securities, which primarily reflect fluctuations in general levels of interest rates. Ratings are relative and subjective and not absolute standards of quality. Securities ratings are based largely on the issuer’s historical financial condition and the rating agencies’ analysis at the time of rating. Consequently, the rating assigned to any particular security is not necessarily a reflection of the issuer’s current financial condition. In light of these risks, the Investment Adviser, in evaluating the creditworthiness of an issuer, whether rated or unrated, will take various factors into consideration, which may include, as applicable, the issuer’s operating history, financial resources and its sensitivity to economic conditions and trends, the market support for the facility financed by the issue, the perceived ability and integrity of the issuer’s management and regulatory matters. Non-investment grade rated securities also present risks based on payment expectations. If an issuer calls the obligation for redemption (often a feature of fixed income securities), the Fund may have to replace the security with a lower yielding security, resulting in a decreased return for investors. Also, as the principal value of bonds and dividend-paying securities moves inversely with movements in interest rates, in the event of rising interest rates the value of the securities held by the Fund may decline proportionately more than a portfolio consisting of higher rated securities. Investments in zero coupon bonds may be more speculative and subject to greater fluctuations in value due to changes in interest rates than bonds that pay interest currently. The Fund may be subject to a greater risk of rising interest rates due to the current period of rising interest rates and recent inflationary price movements. The Federal Reserve has aggressively been raising interest rates which is likely to drive down the prices of below investment grade securities. See “—Fixed Income Securities Risks—Duration and Maturity Risk” and “— General Risks—Interest Rate Risks Generally.” The Fund may purchase securities of companies that are experiencing significant financial or business difficulties, including companies involved in bankruptcy or other reorganization and liquidation proceedings. Although such investments may result in significant financial returns to the Fund, they involve a substantial degree of risk. The level of analytical sophistication, both financial and legal, necessary for successful investments in issuers experiencing significant business and financial difficulties is unusually high. There can be no assurance that the Fund will correctly evaluate the value of the assets collateralizing its investments or the prospects for a successful reorganization or similar action. In any reorganization or liquidation proceeding relating to a portfolio investment, the Fund may lose all or part of its investment or may be required to accept collateral with a value less than the amount of the Fund’s initial investment. As a part of its investments in non-investment grade securities, the Fund may invest in the securities of issuers in default. The Fund invests in securities of issuers in default only when the Investment Adviser believes that such issuers will honor their obligations and emerge from bankruptcy protection and that the value of such issuers’ securities will appreciate. By investing in the securities of issuers in default, the Fund bears the risk that these issuers will not continue to honor their obligations or emerge from bankruptcy protection or that the value of these securities will not otherwise appreciate. In addition to using statistical rating agencies and other sources, the Investment Adviser will also perform its own analysis of issues in seeking investments that it believes to be underrated (and thus higher yielding) in light of the financial condition of the issuer. Its analysis of issuers may include, among other things, current and anticipated cash flow and borrowing requirements, value of assets in relation to historical cost, strength of management, responsiveness to business conditions, credit standing and current anticipated results of operations. In selecting investments for the Fund, the Investment Adviser may also consider general business conditions, anticipated changes in interest rates and the outlook for specific industries. Subsequent to its purchase by the Fund, an issue of securities may cease to be rated or its rating may be reduced. In addition, it is possible that statistical rating agencies might change their ratings of a particular issue to reflect subsequent events on a timely basis. Moreover, such ratings do not assess the risk of a decline in market value. None of these events will require the sale of the securities by the Fund, although the Investment Adviser will consider these events in determining whether the Fund should continue to hold the securities. Fixed income securities, including non-investment grade securities and comparable unrated securities, frequently have call or buy-back features that permit their issuers to call or repurchase the securities from their holders, such as the Fund. If an issuer exercises these rights during periods of declining interest rates, the Fund may have to replace the security with a lower yielding security, thus resulting in a decreased return for the Fund. The market for non-investment grade and comparable unrated securities has at various times, particularly during times of economic recession, experienced substantial reductions in market value and liquidity. Past recessions have adversely affected the ability of certain issuers of such securities to repay principal and pay interest thereon. The market for those securities could react in a similar fashion in the event of any future economic recession. Inflation Risk Smaller Companies Investment Risk As a result, the purchase or sale of more than a limited number of shares of the securities of a smaller company may affect its market price. The Investment Adviser may need a considerable amount of time to purchase or sell its positions in these securities, particularly when other Investment Adviser-managed accounts or other investors are also seeking to purchase or sell them. The securities of smaller capitalization companies generally trade in lower volumes and are subject to greater and more unpredictable price changes than larger capitalization securities or the market as a whole. In addition, smaller capitalization securities may be particularly sensitive to changes in interest rates, borrowing costs and earnings. Investing in smaller capitalization securities requires a longer-term view. Securities of emerging companies may lack an active secondary market and may be subject to more abrupt or erratic price movements than securities of larger, more established companies or stock market averages in general. Competitors of certain companies, which may or may not be in the same industry, may have substantially greater financial resources than the companies in which the Fund may invest. U.S. Government Securities and Credit Rating Downgrade Risk In 2011, S&P lowered its long-term sovereign credit rating on the U.S. to “AA+” from “AAA.” The downgrade by S&P increased volatility in both stock and bond markets, resulting in higher interest rates and higher Treasury yields, and increased the costs of all kinds of debt. On August 1, 2023, Fitch Ratings lowered its long-term sovereign credit rating on the U.S. to “AA+” from “AAA.” This and any further downgrades of U.S. credit ratings could have significant adverse effects on the U.S. economy generally and could result in significant adverse impacts on issuers of securities held by the Fund itself. The Investment Adviser cannot predict the effects of similar events in the future on the U.S. economy and securities markets or on the Fund’s portfolio. The Investment Adviser monitors developments and seeks to manage the Fund’s portfolio in a manner consistent with achieving the Fund’s investment objectives, but there can be no assurance that it will be successful in doing so and the Investment Adviser may not timely anticipate or manage existing, new or additional risks, contingencies or developments. Foreign Securities Risk There may be less available information about a foreign company than a U.S. company. Foreign securities markets may have substantially less volume than U.S. securities markets and some foreign company securities are less liquid than securities of otherwise comparable U.S. companies. A portfolio of foreign securities may also be adversely affected by fluctuations in the rates of exchange between the currencies of different nations and by exchange control regulations. Foreign markets also have different clearance and settlement procedures that could cause the Fund to encounter difficulties in purchasing and selling securities on such markets and may result in the Fund missing attractive investment opportunities or experiencing loss. In addition, a portfolio that includes foreign securities can expect to have a higher expense ratio because of the increased transaction costs on non-U.S. securities markets and the increased costs of maintaining the custody of foreign securities. The Fund also may purchase ADRs or U.S. dollar denominated securities of foreign issuers. ADRs are receipts issued by U.S. banks or trust companies in respect of securities of foreign issuers held on deposit for use in the U.S. securities markets. While ADRs may not necessarily be denominated in the same currency as the securities into which they may be converted, many of the risks associated with foreign securities may also apply to ADRs. In addition, the underlying issuers of certain depositary receipts, particularly unsponsored or unregistered depositary receipts, are under no obligation to distribute shareholder communications to the holders of such receipts, or to pass through to them any voting rights with respect to the deposited securities. The following provides more detail on certain pronounced risks with foreign investing: ● Foreign Currency Risk. the value of these assets measured in U.S. dollars may be affected favorably or unfavorably by changes in currency rates and exchange control regulations. Fluctuations in currency rates may adversely affect the ability of the Investment Adviser to acquire such securities at advantageous prices and may also adversely affect the performance of such assets. Certain non-U.S. currencies, primarily in developing countries, have been devalued in the past and might face devaluation in the future. Currency devaluations generally have a significant and adverse impact on the devaluing country’s economy in the short and intermediate term and on the financial condition and results of companies’ operations in that country. Currency devaluations may also be accompanied by significant declines in the values and liquidity of equity and debt securities of affected governmental and private sector entities generally. To the extent that affected companies have obligations denominated in currencies other than the devalued currency, those companies may also have difficulty in meeting those obligations under such circumstances, which in turn could have an adverse effect upon the value of the Fund’s investments in such companies. There can be no assurance that current or future developments with respect to foreign currency devaluations will not impair the Fund’s investment flexibility, its ability to achieve its investment objectives or the value of certain of its foreign currency-denominated investments. ● Tax Consequences of Foreign Investing. ● EMU and Redenomination Risk. The effects of the collapse of the Euro, or of the exit of one or more countries from the EMU, on the U.S. and global economies and securities markets are impossible to predict and any such events could have a significant adverse impact on the value and risk profile of the Fund’s portfolio. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets, and on the values of the Fund’s portfolio investments. If one or more EMU countries were to stop using the Euro as its primary currency, the Fund’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to foreign currency risk, liquidity risk and valuation risk to a greater extent than similar investments currently denominated in Euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the Euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Fund may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. ● Emerging Markets Risk. ● Eurozone Risk. . ● Brexit Risk. Cooperation Agreement (“UK/EU Trade Agreement”), which came into full force on May 1, 2021 and set out the foundation of the economic and legal framework for trade between the | ||||||||||||||||||||||||
| Effects of Leverage [Text Block] | The following table is furnished in response to requirements of the SEC. 5.375% shares. 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. See “Risk Factors and Special Considerations.” Assumed Return on Portfolio (10 )% (5 )% 0 % 5 % 10 % Corresponding Return to Common Shareholder (14.57 )% (8.17 )% (1.78 )% 4.62 % 11.02 % Common share total return is composed of two elements—the common share distributions paid by the Fund (the amount of which is largely determined by the taxable income of the Fund (including realized gains or losses) after paying interest on any debt and/or dividends on any preferred shares) and unrealized 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 total return. For example, to assume a total return of 0% the Fund must assume that the income it receives on its investments is entirely offset by expenses and losses in the value of those investments. ● Market Discount Risk | ||||||||||||||||||||||||
| Annual Interest Rate [Percent] | 5.375% | ||||||||||||||||||||||||
| Effects of Leverage [Table Text Block] | Assumed Return on Portfolio (10 )% (5 )% 0 % 5 % 10 % Corresponding Return to Common Shareholder (14.57 )% (8.17 )% (1.78 )% 4.62 % 11.02 % | ||||||||||||||||||||||||
| Return at Minus Ten [Percent] | (14.57%) | ||||||||||||||||||||||||
| Return at Minus Five [Percent] | (8.17%) | ||||||||||||||||||||||||
| Return at Zero [Percent] | (1.78%) | ||||||||||||||||||||||||
| Return at Plus Five [Percent] | 4.62% | ||||||||||||||||||||||||
| Return at Plus Ten [Percent] | 11.02% | ||||||||||||||||||||||||
| Effects of Leverage, Purpose [Text Block] | The following table is furnished in response to requirements of the SEC. 5.375% shares. 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. See “Risk Factors and Special Considerations.” Assumed Return on Portfolio (10 )% (5 )% 0 % 5 % 10 % Corresponding Return to Common Shareholder (14.57 )% (8.17 )% (1.78 )% 4.62 % 11.02 % | ||||||||||||||||||||||||
| Share Price [Table Text Block] | The following table sets forth for the quarters indicated Common Share Corresponding Corresponding Quarter Ended High Low High Low High Low December 31, 2021 $ 33.28 $ 25.74 $ 32.52 $ 27.71 2.34 % (7.11 )% March 31, 2022 $ 26.41 $ 21.32 $ 28.56 $ 24.04 (7.53 )% (11.31 )% June 30, 2022 $ 23.24 $ 17.21 $ 25.20 $ 19.80 (7.78 )% (13.08 )% September 30, 2022 $ 20.94 $ 16.86 $ 23.16 $ 19.43 (9.59 )% (13.23 )% December 31, 2022 $ 17.98 $ 16.18 $ 20.52 $ 18.98 (12.38 )% (14.75 )% March 31, 2023 $ 19.11 $ 16.38 $ 21.18 $ 19.33 (9.77 )% (15.26 )% June 30, 2023 $ 17.15 $ 16.07 $ 20.27 $ 18.81 (15.39 )% (14.57 )% September 30, 2023* $ 18.01 $ 15.71 $ 20.29 $ 18.37 (11.24 )% (14.48 )% | ||||||||||||||||||||||||
| Lowest Price or Bid | $ 15.71 | $ 16.07 | $ 16.38 | $ 16.18 | $ 16.86 | $ 17.21 | $ 21.32 | $ 25.74 | |||||||||||||||||
| Highest Price or Bid | 18.01 | 17.15 | 19.11 | 17.98 | 20.94 | 23.24 | 26.41 | 33.28 | |||||||||||||||||
| Lowest Price or Bid, NAV | 18.37 | 18.81 | 19.33 | 18.98 | 19.43 | 19.80 | 24.04 | 27.71 | |||||||||||||||||
| Highest Price or Bid, NAV | $ 20.29 | $ 20.27 | $ 21.18 | $ 20.52 | $ 23.16 | $ 25.20 | $ 28.56 | $ 32.52 | |||||||||||||||||
| Highest Price or Bid, Premium (Discount) to NAV [Percent] | (11.24%) | (15.39%) | (9.77%) | (12.38%) | (9.59%) | (7.78%) | (7.53%) | 2.34% | |||||||||||||||||
| Lowest Price or Bid, Premium (Discount) to NAV [Percent] | (14.48%) | (14.57%) | (15.26%) | (14.75%) | (13.23%) | (13.08%) | (11.31%) | (7.11%) | |||||||||||||||||
| Latest Premium (Discount) to NAV [Percent] | (14.11%) | ||||||||||||||||||||||||
| Capital Stock, Long-Term Debt, and Other Securities [Abstract] | |||||||||||||||||||||||||
| Capital Stock [Table Text Block] | 6. Capital. investments of $1,067,712 and $1,125,238, respectively, and at average discounts of approximately 15.01% and 11.82% from its NAV. For the fiscal year ended October 31, 2021, the Fund did not repurchase any shares. Transactions in common shares of beneficial interest for the fiscal period ended September 30, 2023 and the fiscal years ended October 31, 2022 and 2021 were as follows: Eleven Months Ended Year Ended Year Ended September 30, October 31, October 31, Shares Amount Shares Amount Shares Amount Net increase in net assets from common shares issued upon reinvestment of distributions 53,634 $ 927,330 376,622 $ 9,754,495 192,795 $ 5,662,229 Net increase from repurchase of common shares (64,063 ) (1,067,712 ) (55,950 ) (1,125,238 ) — — Net increase/(decrease) from transactions in Fund shares (10,429 ) $ (140,382 ) 320,672 $ 8,629,257 192,795 $ 5,662,229 On August 9, 2016, the Fund issued 1,200,000 shares of 5.375% Series A Cumulative Preferred (Series A Preferred). At any time, the Fund, at its option, may redeem its Series A Preferred in whole or in part at the redemption price plus an amount equal to the accumulated and unpaid dividends whether or not declared on such shares. In addition, the Board has authorized the repurchase of Series A Preferred Shares in the open market at prices less than the $25 liquidation value per share. During the fiscal period ended September 30, 2023, the Fund repurchased and retired 3,587 Series A Preferred at an investment of $81,994 and at an average discount of approximately 8.61% to the liquidation preference. During the fiscal year ended October 31, 2022, the Fund did not repurchase any Series A Preferred. At September 30, 2023, 1,196,413 Series A Preferred were outstanding and accrued dividends amounted to $22,329. The Fund’s Declaration of Trust, as amended, authorizes the issuance of an unlimited number of Series A Preferred, par value $0.01. The holders of Preferred Shares shares, voting as a single class, will be required to approve any plan of reorganization adversely affecting the preferred stock, and the approval of two-thirds of each class, voting separately, of the Fund’s outstanding voting stock must approve the conversion of the Fund from a closed-end to an open-end investment company. The approval of a majority (as defined in the 1940 Act) of the outstanding preferred shares and a majority (as defined in the 1940 Act) of the Fund’s outstanding voting securities are required to approve certain other actions, including changes in the Fund’s investment objectives or fundamental investment policies. | ||||||||||||||||||||||||
| Outstanding Securities [Table Text Block] | Outstanding Securities The following information regarding the Fund’s authorized shares is as of September 30, 2023. Title of Class Authorized Amount or Amount Exclusive of Common Shares Unlimited — 5,828,029 Series A Cumulative Preferred Shares 1,200,000 — 1,196,413 | ||||||||||||||||||||||||
| Common Stocks [Member] | |||||||||||||||||||||||||
| Capital Stock, Long-Term Debt, and Other Securities [Abstract] | |||||||||||||||||||||||||
| Outstanding Security, Held [Shares] | 5,828,029 | ||||||||||||||||||||||||
| Series A Cumulative Preferred Stock [Member] | |||||||||||||||||||||||||
| Other Annual Expenses [Abstract] | |||||||||||||||||||||||||
| [custom:SeniorSecuritieInvoluntaryLiquidatingPreferencePerUnit] | $ 25 | $ 25 | $ 25 | $ 25 | $ 25 | $ 25 | |||||||||||||||||||
| [custom:SeniorSecuritieAmount] | $ 30,000,000 | $ 30,000,000 | $ 30,000,000 | $ 30,000,000 | $ 30,000,000 | $ 29,910,000 | $ 30,000,000 | $ 30,000,000 | |||||||||||||||||
| [custom:SeniorSecuritiesInvoluntaryLiquidatingPreferencesPerUnit] | $ 25 | $ 25 | |||||||||||||||||||||||
| Financial Highlights [Abstract] | |||||||||||||||||||||||||
| Senior Securities Average Market Value per Unit | $ 24.68 | [5] | $ 25.72 | [5] | $ 25.65 | [5] | $ 25.36 | [5] | $ 25.24 | [5] | $ 23.57 | [5] | $ 25.11 | $ 25.49 | |||||||||||
| Capital Stock, Long-Term Debt, and Other Securities [Abstract] | |||||||||||||||||||||||||
| Outstanding Security, Held [Shares] | 1,200,000 | 1,200,000 | 1,200,000 | 1,200,000 | 1,200,000 | 1,196,000 | |||||||||||||||||||
| Outstanding Security, Not Held [Shares] | 1,200,000 | 1,200,000 | |||||||||||||||||||||||
| [custom:SeniorSecuritieCoveragePerUnit] | $ 123.03 | $ 177.12 | $ 152.94 | $ 138.47 | $ 128.27 | $ 114.42 | $ 131.04 | $ 120.03 | |||||||||||||||||
| Cumulative Preferred Stocks [Member] | |||||||||||||||||||||||||
| Capital Stock, Long-Term Debt, and Other Securities [Abstract] | |||||||||||||||||||||||||
| Security Voting Rights [Text Block] | The holders of Preferred Shares shares, voting as a single class, will be required to approve any plan of reorganization adversely affecting the preferred stock, and the approval of two-thirds of each class, voting separately, of the Fund’s outstanding voting stock must approve the conversion of the Fund from a closed-end to an open-end investment company. The approval of a majority (as defined in the 1940 Act) of the outstanding preferred shares and a majority (as defined in the 1940 Act) of the Fund’s outstanding voting securities are required to approve certain other actions, including changes in the Fund’s investment objectives or fundamental investment policies. | ||||||||||||||||||||||||
| Preferred Stock Restrictions, Other [Text Block] | The Fund’s Declaration of Trust, as amended, authorizes the issuance of an unlimited number of Series A Preferred, par value $0.01. | ||||||||||||||||||||||||
| Purchase Transaction [Member] | |||||||||||||||||||||||||
| Fee Table [Abstract] | |||||||||||||||||||||||||
| Dividend Reinvestment and Cash Purchase Fees | [6] | $ 1.25 | |||||||||||||||||||||||
| Common Shares [Member] | |||||||||||||||||||||||||
| Capital Stock, Long-Term Debt, and Other Securities [Abstract] | |||||||||||||||||||||||||
| Outstanding Security, Title [Text Block] | Common Shares | ||||||||||||||||||||||||
| Outstanding Security, Held [Shares] | |||||||||||||||||||||||||
| Outstanding Security, Not Held [Shares] | 5,828,029 | ||||||||||||||||||||||||
| Series A Cumulative Preferred Shares [Member] | |||||||||||||||||||||||||
| Capital Stock, Long-Term Debt, and Other Securities [Abstract] | |||||||||||||||||||||||||
| Outstanding Security, Title [Text Block] | Series A Cumulative Preferred Shares | ||||||||||||||||||||||||
| Outstanding Security, Authorized [Shares] | 1,200,000 | ||||||||||||||||||||||||
| Outstanding Security, Held [Shares] | |||||||||||||||||||||||||
| Outstanding Security, Not Held [Shares] | 1,196,413 | ||||||||||||||||||||||||
| Market Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Market Risk. industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors which affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Fund. Even when markets perform well, there is no assurance that the investments held by the Fund will increase in value along with the broader market. In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Fund to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown, which could have an adverse impact on the Fund’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including, but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Fund’s investments. Any market disruptions could also prevent the Fund from executing advantageous investment decisions in a timely manner. To the extent that the Fund focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Fund meets their individual financial needs and tolerance for risk. Current market conditions may pose heightened risks with respect to the Fund’s investment in fixed income securities. Interest rates have risen in recent months, and the risk that they may continue to do so is pronounced. Any interest rate increases in the future could cause the value of the Fund to decrease. Recently, inflation levels have been at their highest point in nearly 40 years and the Federal Reserve has been engaged in an aggressive campaign to raise certain benchmark interest rates in an effort to combat inflation. As inflation increases, the real value of the Fund’s common stock and distributions therefore may decline. Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Fund being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. | ||||||||||||||||||||||||
| Convertible Securities Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Convertible Securities Risk The value of a convertible security is influenced by the value of the underlying equity security. Convertible debt securities and preferred stocks may depreciate in value if the market value of the underlying equity security declines or if rates of interest increase. In addition, although debt securities are liabilities of a corporation which the corporation is generally obligated to repay at a specified time, debt securities, particularly convertible debt securities, are often subordinated to the claims of some or all of the other creditors of the corporation. Mandatory conversion securities (securities that automatically convert into equity securities at a future date) may limit the potential for capital appreciation and, in some instances, are subject to complete loss of invested capital. Other innovative convertibles include “equity-linked” securities, which are securities or derivatives that may have fixed, variable or no interest payments prior to maturity, may convert (at the option of the holder or on a mandatory basis) into cash or a combination of cash and common stock, and may be structured to limit the potential for capital appreciation. Equity-linked securities may be illiquid and difficult to value and may be subject to greater credit risk than that of other convertibles. Moreover, mandatory conversion securities and equity-linked securities have increased the sensitivity of the convertible securities market to the volatility of the equity markets and to the special risks of those innovations, which may include risks different from, and possibly greater than, those associated with traditional convertible securities. Preferred stocks are equity securities in the sense that they do not represent a liability of the corporation. In the event of liquidation of the corporation, and after its creditors have been paid or provided for, holders of preferred stock are generally entitled to a preference as to the assets of the corporation before any distribution may be made to the holders of common stock. Debt securities normally do not have voting rights. Preferred stocks may have no voting rights or may have voting rights only under certain circumstances. ● Credit Risk. ● Market Risk. mandatory convertible securities include features which render them more sensitive to price changes of their underlying securities. Thus they expose the Fund to greater downside risk than traditional convertible securities, but generally less than that of the underlying common stock. ● Interest Rate Risk for Convertible Securities. ● Sector Risk. ● Dilution Risk | ||||||||||||||||||||||||
| Synthetic Convertible Instruments Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Synthetic Convertible Instruments Risk | ||||||||||||||||||||||||
| Equity Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Equity Risk | ||||||||||||||||||||||||
| Common Stock Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Common Stock Risk structurally subordinated as to income and residual value to preferred stock, bonds and other debt instruments in a company’s capital structure, in terms of priority to corporate income, and therefore will be subject to greater dividend risk than preferred stock or debt instruments of such issuers. In addition, while common stock has historically generated higher average returns than fixed income securities, common stock has also experienced significantly more volatility in those returns. | ||||||||||||||||||||||||
| Preferred Stock Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Preferred Stock Risk ● Deferral. ● Non-Cumulative Dividends. ● Subordination. ● Liquidity. ● Limited Voting Rights. ● Special Redemption Rights. | ||||||||||||||||||||||||
| Warrants And Rights [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Warrants and Rights Investing in rights and warrants can provide a greater potential for profit or loss than an equivalent investment in the underlying security, and thus can be a riskier investment. The value of a right or warrant may decline because of a decline in the value of the underlying security, the passage of time, changes in interest rates or in the dividend or other policies of the Fund whose equity underlies the warrant, a change in the perception as to the future price of the underlying security, or any combination thereof. Rights and warrants generally pay no dividends and confer no voting or other rights other than the right to purchase the underlying security. | ||||||||||||||||||||||||
| Fixed Income Securities Risks [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Fixed Income Securities Risks ● Interest Rate Risk. ● Issuer Risk. ● Credit Risk. ● Prepayment Risk. ● Reinvestment Risk. ● Duration and Maturity Risk. Specifically, duration measures the anticipated percentage change in NAV that is expected for every percentage point change in interest rates. The two have an inverse relationship. Duration can be a useful tool to estimate anticipated price changes to a fixed pool of income securities associated with changes in interest rates. For example, a duration of five years means that a 1% decrease in interest rates will increase the NAV of the portfolio by approximately 5%; if interest rates increase by 1%, the NAV will decrease by 5%. However, in a managed portfolio of fixed income securities having differing interest or dividend rates or payment schedules, maturities, redemption provisions, call or prepayment provisions and credit qualities, actual price changes in response to changes in interest rates may differ significantly from a duration-based estimate at any given time. Actual price movements experienced by a portfolio of fixed income securities will be affected by how interest rates move (i.e., changes in the relationship of long-term interest rates to short-term interest rates), the magnitude of any move in interest rates, actual and anticipated prepayments of principal through call or redemption features, the extension of maturities through restructuring, the sale of securities for portfolio management purposes, the reinvestment of proceeds from prepayments on and from sales of securities, and credit quality-related considerations whether associated with financing costs to lower credit quality borrowers or otherwise, as well as other factors. Accordingly, while duration maybe a useful tool to estimate potential price movements in relation to changes in interest rates, investors are cautioned that duration alone will not predict actual changes in the net asset or market value of the Fund’s shares and that actual price movements in the Fund’s portfolio may differ significantly from duration-based estimates. Duration differs from maturity in that it takes into account a security’s yield, coupon payments and its principal payments in addition to the amount of time until the security matures. As the value of a security changes over time, so will its duration. Prices of securities with longer durations tend to be more sensitive to interest rate changes than securities with shorter durations. In general, a portfolio of securities with a longer duration can be expected to be more sensitive to interest rate changes than a portfolio with a shorter duration. Any decisions as to the targeted duration or maturity of any particular category of investments will be made based on all pertinent market factors at any given time. The Fund may incur costs in seeking to adjust the portfolio average duration or maturity. There can be no assurance that the Investment Adviser’s assessment of current and projected market conditions will be correct or that any strategy to adjust duration or maturity will be successful at any given time. | ||||||||||||||||||||||||
| L I B O R Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | LIBOR Risk In July 2017, the head of the United Kingdom Financial Conduct Authority announced the desire to phase out the use of LIBOR by the end of 2021. LIBOR can no longer be used to calculate new deals as of December 31, 2021. Since December 31, 2021, all sterling, euro, Swiss franc and Japanese yen LIBOR settings and the 1-week and 2-month U.S. dollar LIBOR settings have ceased to be published or are no longer representative. Overnight and 12-month US dollar LIBOR settings permanently ceased as of June 30, 2023. 1-, 3-, and 6-month U.S. dollar LIBOR settings will continue to be published using a synthetic methodology until September 2024. Various financial industry groups have begun planning for the transition away from LIBOR, but there are challenges to converting certain securities and transactions to a new reference rate. Neither the effect of the LIBOR transition process nor its ultimate success can yet be known. As an alternative to LIBOR, the Financial Reporting Council, in conjunction with the Alternative Reference Rates Committee, a steering committee comprised of large U.S. financial institutions, recommended replacing U.S. dollar LIBOR with the Secured Overnight Financing Rate (“SOFR”), a new index calculated by reference to short-term repurchase agreements, backed by Treasury securities. Abandonment of, or modifications to, LIBOR could have adverse impacts on newly issued financial instruments and any of our existing financial instruments which reference LIBOR. Given the inherent differences between LIBOR and SOFR, or any other alternative benchmark rate that may be established, there are many uncertainties regarding a transition from LIBOR, including, but not limited to, the need to amend all contracts with LIBOR as the referenced rate and how this will impact the cost of variable rate debt and certain derivative financial instruments. In addition, SOFR or other replacement rates may fail to gain market acceptance. Any failure of SOFR or alternative reference rates to gain market acceptance could adversely affect the return on, value of and market for securities linked to such rates. Neither the effect of the LIBOR transition process nor its ultimate success can yet be known. The transition process might lead to increased volatility and illiquidity in markets for, and reduce the effectiveness of, new hedges placed against instruments whose terms currently include LIBOR. 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. Moreover, these alternative rate-setting provisions may not be designed for regular use in an environment where LIBOR ceases to be published, and may be an ineffective fallback following the discontinuation of LIBOR. On March 15, 2022, President Biden signed into law the Consolidated Appropriations Act of 2022, which among other things, provides for the use of interest rates based on SOFR in certain contracts currently based on LIBOR and a safe harbor from liability for utilizing SOFR-based interest rates as a replacement for LIBOR. The elimination of LIBOR could have an adverse impact on the market value of and/or transferability of any LIBOR-linked securities, loans, and other financial obligations or extensions of credit held by or due to us or on our overall financial condition or results of operations. | ||||||||||||||||||||||||
| Interest Rate Risk Generally [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Interest Rate Risk Generally The magnitude of these fluctuations in the market price of bonds and other income- or dividend-paying securities is generally greater for those securities with longer maturities. Fluctuations in the market price of the Fund’s investments will not affect interest income derived from instruments already owned by the Fund, but will be reflected in the Fund’s net asset value. The Fund may lose money if short-term or long-term interest rates rise sharply in a manner not anticipated by Fund management. To the extent the Fund invests in debt securities that may be prepaid at the option of the obligor, the sensitivity of such securities to changes in interest rates may increase (to the detriment of the Fund) when interest rates rise. Moreover, because rates on certain floating rate debt securities typically reset only periodically, changes in prevailing interest rates (and particularly sudden and significant changes) can be expected to cause some fluctuations in the net asset value of the Fund to the extent that it invests in floating rate debt securities. These basic principles of bond prices also apply to U.S. government securities. A security backed by the “full faith and credit” of the U.S. government is guaranteed only as to its stated interest rate and face value at maturity, not its current market price. Just like other income- or dividend-paying securities, government-guaranteed securities will fluctuate in value when interest rates change. The Fund’s use of leverage will tend to increase the Fund’s interest rate risk. The Fund may invest in variable and floating rate debt instruments, which generally are less sensitive to interest rate changes than longer duration fixed rate instruments, but may decline in value in response to rising interest rates if, for example, the rates at which they pay interest do not rise as much, or as quickly, as market interest rates in general. Conversely, variable and floating rate instruments generally will not increase in value if interest rates decline. The Fund also may invest in inverse floating rate debt securities, which may decrease in value if interest rates increase, and which also may exhibit greater price volatility than fixed rate debt obligations with similar credit quality. To the extent the Fund holds variable or floating rate instruments, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities, which may adversely affect the net asset value of the Fund’s common shares. | ||||||||||||||||||||||||
| Corporate Bonds Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Corporate Bonds Risk | ||||||||||||||||||||||||
| Non Investment Grade Securities Principal [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Non-Investment Grade Securities government securities or securities of investment grade issuers because they are subject to greater risks than these securities. These risks, which reflect their speculative character, include the following: ● greater volatility; ● greater credit risk and risk of default; ● potentially greater sensitivity to general economic or industry conditions; ● potential lack of attractive resale opportunities (illiquidity); and ● additional expenses to seek recovery from issuers who default. In addition, the prices of these non-investment grade securities are more sensitive to negative developments, such as a decline in the issuer’s revenues or a general economic downturn, than are the prices of higher grade securities. Non-investment grade securities tend to be less liquid than investment grade securities. The market value of non-investment grade securities may be more volatile than the market value of investment grade securities and generally tends to reflect the market’s perception of the creditworthiness of the issuer and short-term market developments to a greater extent than investment grade securities, which primarily reflect fluctuations in general levels of interest rates. Ratings are relative and subjective and not absolute standards of quality. Securities ratings are based largely on the issuer’s historical financial condition and the rating agencies’ analysis at the time of rating. Consequently, the rating assigned to any particular security is not necessarily a reflection of the issuer’s current financial condition. In light of these risks, the Investment Adviser, in evaluating the creditworthiness of an issuer, whether rated or unrated, will take various factors into consideration, which may include, as applicable, the issuer’s operating history, financial resources and its sensitivity to economic conditions and trends, the market support for the facility financed by the issue, the perceived ability and integrity of the issuer’s management and regulatory matters. Non-investment grade rated securities also present risks based on payment expectations. If an issuer calls the obligation for redemption (often a feature of fixed income securities), the Fund may have to replace the security with a lower yielding security, resulting in a decreased return for investors. Also, as the principal value of bonds and dividend-paying securities moves inversely with movements in interest rates, in the event of rising interest rates the value of the securities held by the Fund may decline proportionately more than a portfolio consisting of higher rated securities. Investments in zero coupon bonds may be more speculative and subject to greater fluctuations in value due to changes in interest rates than bonds that pay interest currently. The Fund may be subject to a greater risk of rising interest rates due to the current period of rising interest rates and recent inflationary price movements. The Federal Reserve has aggressively been raising interest rates which is likely to drive down the prices of below investment grade securities. See “—Fixed Income Securities Risks—Duration and Maturity Risk” and “— General Risks—Interest Rate Risks Generally.” The Fund may purchase securities of companies that are experiencing significant financial or business difficulties, including companies involved in bankruptcy or other reorganization and liquidation proceedings. Although such investments may result in significant financial returns to the Fund, they involve a substantial degree of risk. The level of analytical sophistication, both financial and legal, necessary for successful investments in issuers experiencing significant business and financial difficulties is unusually high. There can be no assurance that the Fund will correctly evaluate the value of the assets collateralizing its investments or the prospects for a successful reorganization or similar action. In any reorganization or liquidation proceeding relating to a portfolio investment, the Fund may lose all or part of its investment or may be required to accept collateral with a value less than the amount of the Fund’s initial investment. As a part of its investments in non-investment grade securities, the Fund may invest in the securities of issuers in default. The Fund invests in securities of issuers in default only when the Investment Adviser believes that such issuers will honor their obligations and emerge from bankruptcy protection and that the value of such issuers’ securities will appreciate. By investing in the securities of issuers in default, the Fund bears the risk that these issuers will not continue to honor their obligations or emerge from bankruptcy protection or that the value of these securities will not otherwise appreciate. In addition to using statistical rating agencies and other sources, the Investment Adviser will also perform its own analysis of issues in seeking investments that it believes to be underrated (and thus higher yielding) in light of the financial condition of the issuer. Its analysis of issuers may include, among other things, current and anticipated cash flow and borrowing requirements, value of assets in relation to historical cost, strength of management, responsiveness to business conditions, credit standing and current anticipated results of operations. In selecting investments for the Fund, the Investment Adviser may also consider general business conditions, anticipated changes in interest rates and the outlook for specific industries. Subsequent to its purchase by the Fund, an issue of securities may cease to be rated or its rating may be reduced. In addition, it is possible that statistical rating agencies might change their ratings of a particular issue to reflect subsequent events on a timely basis. Moreover, such ratings do not assess the risk of a decline in market value. None of these events will require the sale of the securities by the Fund, although the Investment Adviser will consider these events in determining whether the Fund should continue to hold the securities. Fixed income securities, including non-investment grade securities and comparable unrated securities, frequently have call or buy-back features that permit their issuers to call or repurchase the securities from their holders, such as the Fund. If an issuer exercises these rights during periods of declining interest rates, the Fund may have to replace the security with a lower yielding security, thus resulting in a decreased return for the Fund. The market for non-investment grade and comparable unrated securities has at various times, particularly during times of economic recession, experienced substantial reductions in market value and liquidity. Past recessions have adversely affected the ability of certain issuers of such securities to repay principal and pay interest thereon. The market for those securities could react in a similar fashion in the event of any future economic recession. | ||||||||||||||||||||||||
| Inflation Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Inflation Risk | ||||||||||||||||||||||||
| Smaller Companies Investment Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Smaller Companies Investment Risk As a result, the purchase or sale of more than a limited number of shares of the securities of a smaller company may affect its market price. The Investment Adviser may need a considerable amount of time to purchase or sell its positions in these securities, particularly when other Investment Adviser-managed accounts or other investors are also seeking to purchase or sell them. The securities of smaller capitalization companies generally trade in lower volumes and are subject to greater and more unpredictable price changes than larger capitalization securities or the market as a whole. In addition, smaller capitalization securities may be particularly sensitive to changes in interest rates, borrowing costs and earnings. Investing in smaller capitalization securities requires a longer-term view. Securities of emerging companies may lack an active secondary market and may be subject to more abrupt or erratic price movements than securities of larger, more established companies or stock market averages in general. Competitors of certain companies, which may or may not be in the same industry, may have substantially greater financial resources than the companies in which the Fund may invest. | ||||||||||||||||||||||||
| U S Government Securities And Credit Rating Downgrade Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | U.S. Government Securities and Credit Rating Downgrade Risk In 2011, S&P lowered its long-term sovereign credit rating on the U.S. to “AA+” from “AAA.” The downgrade by S&P increased volatility in both stock and bond markets, resulting in higher interest rates and higher Treasury yields, and increased the costs of all kinds of debt. On August 1, 2023, Fitch Ratings lowered its long-term sovereign credit rating on the U.S. to “AA+” from “AAA.” This and any further downgrades of U.S. credit ratings could have significant adverse effects on the U.S. economy generally and could result in significant adverse impacts on issuers of securities held by the Fund itself. The Investment Adviser cannot predict the effects of similar events in the future on the U.S. economy and securities markets or on the Fund’s portfolio. The Investment Adviser monitors developments and seeks to manage the Fund’s portfolio in a manner consistent with achieving the Fund’s investment objectives, but there can be no assurance that it will be successful in doing so and the Investment Adviser may not timely anticipate or manage existing, new or additional risks, contingencies or developments. | ||||||||||||||||||||||||
| Foreign Securities Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Foreign Securities Risk There may be less available information about a foreign company than a U.S. company. Foreign securities markets may have substantially less volume than U.S. securities markets and some foreign company securities are less liquid than securities of otherwise comparable U.S. companies. A portfolio of foreign securities may also be adversely affected by fluctuations in the rates of exchange between the currencies of different nations and by exchange control regulations. Foreign markets also have different clearance and settlement procedures that could cause the Fund to encounter difficulties in purchasing and selling securities on such markets and may result in the Fund missing attractive investment opportunities or experiencing loss. In addition, a portfolio that includes foreign securities can expect to have a higher expense ratio because of the increased transaction costs on non-U.S. securities markets and the increased costs of maintaining the custody of foreign securities. The Fund also may purchase ADRs or U.S. dollar denominated securities of foreign issuers. ADRs are receipts issued by U.S. banks or trust companies in respect of securities of foreign issuers held on deposit for use in the U.S. securities markets. While ADRs may not necessarily be denominated in the same currency as the securities into which they may be converted, many of the risks associated with foreign securities may also apply to ADRs. In addition, the underlying issuers of certain depositary receipts, particularly unsponsored or unregistered depositary receipts, are under no obligation to distribute shareholder communications to the holders of such receipts, or to pass through to them any voting rights with respect to the deposited securities. The following provides more detail on certain pronounced risks with foreign investing: ● Foreign Currency Risk. the value of these assets measured in U.S. dollars may be affected favorably or unfavorably by changes in currency rates and exchange control regulations. Fluctuations in currency rates may adversely affect the ability of the Investment Adviser to acquire such securities at advantageous prices and may also adversely affect the performance of such assets. Certain non-U.S. currencies, primarily in developing countries, have been devalued in the past and might face devaluation in the future. Currency devaluations generally have a significant and adverse impact on the devaluing country’s economy in the short and intermediate term and on the financial condition and results of companies’ operations in that country. Currency devaluations may also be accompanied by significant declines in the values and liquidity of equity and debt securities of affected governmental and private sector entities generally. To the extent that affected companies have obligations denominated in currencies other than the devalued currency, those companies may also have difficulty in meeting those obligations under such circumstances, which in turn could have an adverse effect upon the value of the Fund’s investments in such companies. There can be no assurance that current or future developments with respect to foreign currency devaluations will not impair the Fund’s investment flexibility, its ability to achieve its investment objectives or the value of certain of its foreign currency-denominated investments. ● Tax Consequences of Foreign Investing. ● EMU and Redenomination Risk. The effects of the collapse of the Euro, or of the exit of one or more countries from the EMU, on the U.S. and global economies and securities markets are impossible to predict and any such events could have a significant adverse impact on the value and risk profile of the Fund’s portfolio. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets, and on the values of the Fund’s portfolio investments. If one or more EMU countries were to stop using the Euro as its primary currency, the Fund’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to foreign currency risk, liquidity risk and valuation risk to a greater extent than similar investments currently denominated in Euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the Euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Fund may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. ● Emerging Markets Risk. ● Eurozone Risk. . ● Brexit Risk. Cooperation Agreement (“UK/EU Trade Agreement”), which came into full force on May 1, 2021 and set out the foundation of the economic and legal framework for trade between the United Kingdom and the EU. As the UK/EU Trade Agreement is a new legal framework, the implementation of the UK/EU Trade Agreement may result in uncertainty in its application and periods of volatility in both the United Kingdom and wider European markets. The United Kingdom’s exit from the EU is expected to result in additional trade costs and disruptions in this trading relationship. Furthermore, there is the possibility that either party may impose tariffs on trade in the future in the event that regulatory standards between the EU and the UK diverge. The terms of the future relationship may cause continued uncertainty in the global financial markets, and adversely affect our ability, and the ability of our portfolio companies, to execute our respective strategies and to receive attractive returns. ● In particular, currency volatility may mean that our returns and the returns of our portfolio companies will be adversely affected by market movements and may make it more difficult, or more expensive, for us to implement appropriate currency hedging. Potential declines in the value of the British Pound and/or the euro against other currencies, along with the potential downgrading of the United Kingdom’s sovereign credit rating, may also have an impact on the performance of any of our portfolio companies located in the United Kingdom or Europe. ● In addition, certain European countries have recently experienced negative interest rates on certain fixed-income instruments. A negative interest rate policy is an unconventional central bank monetary policy tool where nominal target interest rates are set with a negative value (i.e., below zero percent) intended to help create self-sustaining growth in the local economy. Negative interest rates may result in heightened market volatility and may detract from the Fund’s performance to the extent the Fund is exposed to such interest rates. Among other things, these developments adversely affected the value and exchange rate of the euro and pound sterling, and any similar developments may continue to sig-nificantly affect the economies of all EU countries, which in turn may have a material adverse effect on the Fund’s investments in such countries, other countries that depend on EU countries for significant amounts of trade or investment, or issuers with exposure to debt issued by certain EU countries To the extent the Fund has exposure to European markets or to transactions tied to the value of the euro, these events could negatively affect the value and liquidity of the Fund’s investments. All of these developments may continue to significantly affect the economies of all EU countries, which in turn may have a material adverse effect on the Fund’s investments in such countries, other countries that depend on EU countries for significant amounts of trade or investment, or issuers with exposure to debt issued by certain EU countries. | ||||||||||||||||||||||||
| Restricted And Illiquid Securities Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Restricted and Illiquid Securities Risk realize a favorable price upon disposition of unregistered securities, and at times might make disposition of such securities impossible. The Fund may be unable to sell illiquid investments when it desires to do so, resulting in the Fund obtaining a lower price or being required to retain the investment. Illiquid investments generally must be valued at fair value, which is inherently less precise than utilizing market values for liquid investments, and may lead to differences between the price a security is valued for determining the Fund’s net asset value and the price the Fund actually receives upon sale. | ||||||||||||||||||||||||
| Special Risks Related To Investment In Derivatives [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Special Risks Related to Investment in Derivatives ● dependence on the Investment Adviser’s ability to predict correctly movements in the direction of the relevant measure; ● imperfect correlation between the price of the derivative instrument and movements in the prices of the referenced assets; ● the fact that skills needed to use these strategies are different from those needed to select portfolio securities; ● the possible absence of a liquid secondary market for any particular instrument at any time; ● the possible need to defer closing out certain positions to avoid adverse tax consequences; ● the possible inability of the Fund to purchase or sell a security or instrument at a time that otherwise would be favorable for it to do so, or the possible need for the Fund to sell a security or instrument at a disadvantageous time due to a need for the Fund to remain in compliance with the 1940 Act restrictions regarding derivatives transactions; and ● the creditworthiness of counterparties. Options, futures contracts, swaps contracts, and options thereon and forward contracts on securities and currencies may be traded on foreign exchanges. Such transactions may not be regulated as effectively as similar transactions in the United States, may not involve a clearing mechanism and related guarantees, and are subject to the risk of governmental actions affecting trading in, or the prices of, foreign securities. The value of such positions also could be adversely affected by (i) other complex foreign political, legal and economic factors, (ii) lesser availability than in the United States of data on which to make trading decisions, (iii) delays in the ability of the Fund to act upon economic events occurring in the foreign markets during non-business hours in the United States, (iv) the imposition of different exercise and settlement terms and procedures and margin requirements than in the United States, and (v) less trading volume. Exchanges on which options, futures, swaps and options on futures or swaps are traded may impose limits on the positions that the Fund may take in certain circumstances. Many over-the-counter (“OTC”) derivatives are valued on the basis of dealers’ pricing of these instruments. However, the price at which dealers value a particular derivative and the price which the same dealers would actually be willing to pay for such derivative should the Fund wish or be forced to sell such position may be materially different. Such differences can result in an overstatement of the Fund’s net asset value and may materially adversely affect the Fund in situations in which the Fund is required to sell derivative instruments. Exchange-traded derivatives and OTC derivative transactions submitted for clearing through a central counterparty have become subject to minimum initial and variation margin requirements set by the relevant clearinghouse, as well as possible margin requirements mandated by the SEC or the CFTC. These regulators also have broad discretion to impose margin requirements on non-cleared OTC derivatives. These margin requirements will increase the overall costs for the Fund. While hedging reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund’s hedging transactions will be effective. Derivatives may give rise to a form of leverage and may expose the Fund to greater risk and increase its costs. Future CFTC or SEC rulemakings could potentially further limit or completely restrict the Fund’s ability to use these instruments as a part of the Fund’s investment strategy, increase the costs of using these instruments or make them less effective. Limits or restrictions applicable to the counterparties with which the Fund engages in derivative transactions could also prevent the Fund from using these instruments or affect the pricing or other factors relating to these instruments or may change the availability of certain investments. New regulation may make derivatives more costly, may limit the availability of derivatives, or may otherwise adversely affect the value or performance of derivatives. | ||||||||||||||||||||||||
| Counterparty Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Counterparty Risk The counterparty risk for cleared derivatives is generally lower than for uncleared OTC derivative transactions since generally a clearing organization becomes substituted for each counterparty to a cleared derivative contract and, in effect, guarantees the parties’ performance under the contract as each party to a trade looks only to the clearing organization for performance of financial obligations under the derivative contract. However, there can be no assurance that a clearing organization, or its members, will satisfy its obligations 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. In addition, cleared derivative transactions benefit from daily marking-to-market and settlement, and segregation and minimum capital requirements applicable to intermediaries. Uncleared OTC derivative transactions generally do not benefit from such protections. This exposes the Fund to the risk that a counterparty will not settle a transaction in accordance with its terms and conditions because of a dispute over the terms of the contract (whether or not bona fide) or because of a credit or liquidity problem, thus causing the Fund to suffer a loss. Such “counterparty risk” is accentuated for contracts with longer maturities where events may intervene to prevent settlement, or where the Fund has concentrated its transactions with a single or small group of counterparties. | ||||||||||||||||||||||||
| Short Sales Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Short Sales Risk 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. 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. In September 2008, in response to spreading turmoil in the financial markets, the SEC temporarily banned short selling in the stocks of numerous financial services companies, and also promulgated new disclosure requirements with respect to short positions held by investment managers. The SEC’s temporary ban on short selling of such stocks has since expired, but should similar restrictions and/or additional disclosure requirements be promulgated, especially if market turmoil occurs, the Fund may be forced to cover short positions more quickly than otherwise intended and may suffer losses as a result. Such restrictions may also adversely affect the ability of the Fund to execute its investment strategies generally. Similar emergency orders were also instituted in non-U.S. markets in response to increased volatility. The Fund’s ability to engage in short sales is also restricted by various regulatory requirements relating to short sales. | ||||||||||||||||||||||||
| Significant Holdings Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Significant Holdings Risk | ||||||||||||||||||||||||
| Healthcare Sector Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Healthcare Sector Risk on patent protection. The expiration of a company’s patents may adversely affect that company’s profitability. Many healthcare companies are subject to extensive civil litigation based on product liability and similar claims. Healthcare companies are subject to competitive forces that may make it difficult to raise prices and, in fact, may result in price discounting. Many new products in the healthcare sector may be subject to regulatory approvals. The process of obtaining such approvals may be long and costly, and such efforts ultimately may be unsuccessful. Companies in the healthcare sector may be thinly capitalized and may be susceptible to product obsolescence. | ||||||||||||||||||||||||
| Information Technology Sector Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Information Technology Sector Risk The securities of information technology companies tend to exhibit a greater degree of market risk and sharp price fluctuations than other types of securities. These securities may fall in and out of favor with investors rapidly, which may cause sudden selling and dramatically lower market prices. Technology securities also may be affected adversely by changes in technology, consumer and business purchasing patterns, government regulation, product and/or service obsolescence, unpredictable changes in growth rates and competition for the services of qualified personnel. In addition, a rising interest rate environment tends to negatively affect information technology companies. These companies having high market valuations may appear less attractive to investors, which may cause sharp decreases in their market prices. Further, those information technology companies seeking to finance expansion would have increased borrowing costs, which may negatively impact earnings. | ||||||||||||||||||||||||
| Financial Services Company Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Financial Services Company Risk The profitability of many types of financial services companies may be adversely affected in certain market cycles, including periods of rising interest rates, which may restrict the availability and increase the cost of capital, and declining economic conditions, which may cause credit losses due to financial difficulties of borrowers. Financial services companies are also subject to extensive government regulation, including policy and legislative changes in the United States and other countries. Additional risks include the effects of changes in interest rates on the profitability of financial services companies, the rate of corporate and consumer debt defaults, price competition, governmental limitations on a company’s loans, other financial commitments, product lines and other operations, and recent ongoing changes in financial services companies (including consolidations, development of new products and changes to such companies’ regulatory framework). Some financial services companies have recently experienced significant losses in value and the possible recapitalization of such companies may present greater risks of loss. Insurance companies have additional risks, such as heavy price competition, claims activity and marketing competition, and can be particularly sensitive to specific events such as man-made and natural disasters (including weather catastrophes), terrorism, mortality risks and morbidity rates. | ||||||||||||||||||||||||
| Leverages Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Leverage Risk | ||||||||||||||||||||||||
| Leverage Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Leverage Risk The Fund’s leveraged capital structure creates special risks not associated with unleveraged funds having a similar investment objective and policies. These include the possibility of greater loss and the likelihood of higher volatility of the net asset value of the Fund and the asset coverage for the preferred shares. Such volatility may increase the likelihood of the Fund having to sell investments in order to meet its obligations to make distributions on the preferred shares or principal or interest payments on debt securities, or to redeem preferred shares or repay debt, when it may be disadvantageous to do so. The Fund’s use of leverage may require it to sell portfolio investments at inopportune times in order to raise cash to redeem preferred shares or otherwise de-leverage so as to maintain required asset coverage amounts or comply with the mandatory redemption terms of any outstanding preferred shares. The use of leverage magnifies both the favorable and unfavorable effects of price movements in the investments made by the Fund. To the extent that the Fund employs leverage in its investment operations, the Fund is subject to substantial risk of loss. The Fund cannot assure you that borrowings or the issuance of preferred shares or notes will result in a higher yield or return to the holders of the common shares. Also, since the Fund utilizes leverage, a decline in net asset value could affect the ability of the Fund to make common share distributions and such a failure to make distributions could result in the Fund ceasing to qualify as a RIC under the Code. Any decline in the net asset value the Fund’s investments would be borne entirely by the holders of common shares. Therefore, if the market value of the Fund’s portfolio declines, the leverage will result in a greater decrease in net asset value to the holders of common shares than if the Fund were not leveraged. This greater net asset value decrease will also tend to cause a greater decline in the market price for the common shares. The Fund might be in danger of failing to maintain the required asset coverage of its borrowings, notes or preferred shares, or of losing its ratings on its notes or preferred shares or, in an extreme case, the Fund’s current investment income might not be sufficient to meet the distribution or interest requirements on the preferred shares, or notes. In order to counteract such an event, the Fund might need to liquidate investments in order to fund a redemption of some or all of the preferred shares or notes. ● Preferred Share and Note Risk. In addition, the Fund would pay (and the holders of common shares will bear) all costs and expenses relating to the issuance and ongoing maintenance of the preferred shares or notes, including the advisory fees on the incremental assets attributable to the preferred shares or notes. Holders of preferred shares and notes may have different interests than holders of common shares and may at times have disproportionate influence over the Fund’s affairs. As provided in the 1940 Act and subject to certain exceptions, the Fund may issue senior securities (which may be stock, such as preferred shares, and/or securities representing debt, such as notes) only if immediately after such issuance the value of the Fund’s total assets, less certain ordinary course liabilities, exceeds 300% of the amount of the debt outstanding (i.e., for every dollar of indebtedness outstanding, the Fund is required to have at least three dollars of assets) and exceeds 200% of the amount of preferred shares and debt outstanding (i.e., for every dollar in liquidation preference of preferred stock outstanding, the Fund is required to have two dollars of assets), which is referred to as the “asset coverage” required by the 1940 Act. In the event the Fund fails to maintain an asset coverage of 100% for any notes outstanding for certain periods of time, the 1940 Act requires that either an event of default be declared or that the holders of such notes have the right to elect a majority of the Fund’s Trustees until asset coverage recovers to 110%. In addition, holders of preferred shares, voting separately as a single class, have the right (subject to the rights of noteholders) to elect two members of the Board at all times and in the event dividends become two full years in arrears would have the right to elect a majority of the Trustees until such arrearage is completely eliminated. In addition, preferred shareholders have class voting rights on certain matters, including changes in fundamental investment restrictions and conversion of the Fund to open-end status, and accordingly can veto any such changes. Further, interest on notes will be payable when due as described in a Prospectus Supplement and if the Fund does not pay interest when due, it will trigger an event of default and the Fund expects to be restricted from declaring dividends and making other distributions with respect to common shares and preferred shares. Upon the occurrence and continuance of an event of default, the holders of a majority in principal amount of a series of outstanding notes or the trustee will be able to declare the principal amount of that series of notes immediately due and payable upon written notice to the Fund. The 1940 Act also generally restricts the Fund from declaring distributions on, or repurchasing, common or preferred shares unless notes have an asset coverage of 300% (200% in the case of declaring distributions on preferred shares). The Fund’s common shares are structurally subordinated as to income and residual value to any preferred shares or notes in the Fund’s capital structure, in terms of priority to income and payment in liquidation. Restrictions imposed on the declarations and payment of dividends or other distributions to the holders of the Fund’s common shares and preferred shares, both by the 1940 Act and by requirements imposed by rating agencies, might impair the Fund’s ability to maintain its qualification as a RIC for U.S. federal income tax purposes. While the Fund intends to redeem its preferred shares or notes to the extent necessary to enable the Fund to distribute its income as required to maintain its qualification as a RIC under the Code, there can be no assurance that such actions can be effected in time to meet the Code requirements. Portfolio Guidelines of Rating Agencies for Preferred Shares and/or Credit Facility. Impact on Common Shares. | ||||||||||||||||||||||||
| Market Discount Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Market Discount Risk | ||||||||||||||||||||||||
| Long Term Objective Not A Complete Investment Program [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Long Term Objective; Not a Complete Investment Program investment program. Each shareholder should take into account the Fund’s investment objectives as well as the shareholder’s other investments when considering an investment in the Fund. | ||||||||||||||||||||||||
| Management Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Management Risk | ||||||||||||||||||||||||
| Decision Making Authority Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Decision-Making Authority Risk | ||||||||||||||||||||||||
| Dependence On Key Personnel [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Dependence on Key Personnel | ||||||||||||||||||||||||
| Market Disruption And Geopolitical Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Market Disruption and Geopolitical Risk Risks resulting from any future debt or other economic crisis could also have a detrimental impact on the global economy, the financial condition of financial institutions and the Fund’s business, financial condition and results of operation. Market and economic disruptions have affected, and may in the future affect, consumer confidence levels and spending, personal bankruptcy rates, levels of incurrence and default on consumer debt and home prices, among other factors. To the extent uncertainty regarding the U.S. or global economy negatively impacts consumer confidence and consumer credit factors, the Fund could be significantly and adversely affected. Downgrades to the credit ratings of major banks could result in increased borrowing costs for such banks and negatively affect the broader economy. Moreover, Federal Reserve policy, including with respect to certain interest rates, may also adversely affect the value, volatility and liquidity of dividend- and interest-paying securities. Market volatility, rising interest rates and/or a return to unfavorable economic conditions could impair the Fund’s ability to achieve its investment objectives. The occurrence of events similar to those in recent years, such as localized wars, instability, new and ongoing pandemics (such as COVID-19), epidemics or outbreaks of infectious diseases in certain parts of the world, and catastrophic events such as fires, floods, earthquakes, tornadoes, hurricanes and global health epidemics, terrorist attacks in the U.S. and around the world, social and political discord, debt crises sovereign debt downgrades, increasingly strained relations between the U.S. and a number of foreign countries, new and continued political unrest in various countries, the exit or potential exit of one or more countries from the EU or the EMU, continued changes in the balance of political power among and within the branches of the U.S. government, government shutdowns, 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 U.S. and worldwide. In particular, the consequences of the Russian military invasion of Ukraine, the impact on inflation and increased disruption to supply chains and energy resources may impact the Fund’s portfolio companies, result in an economic downturn or recession either globally or locally in the U.S. or other economies, reduce business activity, spawn additional conflicts (whether in the form of traditional military action, reignited “cold” wars or in the form of virtual warfare such as cyberattacks) with similar and perhaps wider ranging impacts and consequences and have an adverse impact on the Fund’s returns and net asset values. In response to the conflict between Russia and Ukraine, the U.S. and other countries have imposed sanctions or other restrictive actions against Russia, Russian-backed separatist regions in Ukraine, and certain banks, companies, government officials and other individuals in Russia and Belarus. Any of the above factors, including sanctions, export controls, tariffs, trade wars and other governmental actions, could have a material adverse effect on the Fund. The Fund has no way to predict the duration or outcome of the situation, as the conflict and government reactions are rapidly developing and beyond the Fund’s control. Prolonged unrest, military activities, or broad-based sanctions could have a material adverse effect on companies in which the Fund invests. Such consequences also may increase such companies’ funding costs or limit their access to the capital markets. The current political climate has intensified concerns about a potential trade war between China and the U.S., as each country has imposed tariffs on the other country’s products. These actions may trigger a significant reduction in international trade, the oversupply of certain manufactured goods, substantial price reductions of goods and possible failure of individual companies and/or large segments of China’s export industry, which could have a negative impact on the Fund’s performance. U.S. companies that source material and goods from China and those that make large amounts of sales in China would be particularly vulnerable to an escalation of trade tensions. 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. Any of these effects could have a material adverse effect on the Fund. | ||||||||||||||||||||||||
| Economic Events And Market Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Economic Events and Market Risk Risks resulting from any future debt or other economic crisis could also have a detrimental impact on the global economic recovery, the financial condition of financial institutions and our business, financial condition and results of operation. Market and economic disruptions have affected, and may in the future affect, consumer confidence levels and spending, personal bankruptcy rates, levels of incurrence and default on consumer debt and home prices, among other factors. To the extent uncertainty regarding the U.S. or global economy negatively impacts consumer confidence and consumer credit factors, our business, financial condition and results of operations could be significantly and adversely affected. Downgrades to the credit ratings of major banks could result in increased borrowing costs for such banks and negatively affect the broader economy. Moreover, Federal Reserve policy, including with respect to certain interest rates, may also adversely affect the value, volatility and liquidity of dividend- and interest-paying securities. Market volatility, rising interest rates and/or a return to unfavorable economic conditions could impair the Fund’s ability to achieve its investment objectives. | ||||||||||||||||||||||||
| Regulation And Government Intervention Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Regulation and Government Intervention Risk Additional risks arising from the differences in expressed policy preferences among the various constituencies in the branches of the U.S. government has led in the past, and may lead in the future, to short-term or prolonged policy impasses, which could, and has, resulted in shutdowns of the U.S. federal government. U.S. federal government shutdowns, especially prolonged shutdowns, could have a significant adverse impact on the economy in general and could impair the ability of issuers to raise capital in the securities markets. Any of these effects could have a material adverse effect on the Fund’s net asset value. In addition, the rules dealing with the U.S. federal income taxation are constantly under review by persons involved in the legislative process and by the IRS and the U.S. Treasury Department. The Tax Cuts and Jobs Act made substantial changes to the Code. Among those changes were a significant permanent reduction in the generally applicable corporate tax rate, changes in the taxation of individuals and other non-corporate taxpayers that generally but not universally reduce their taxes on a temporary basis subject to “sunset” provisions, the elimination or modification of various previously allowed deductions (including substantial limitations on the deductibility of interest and, in the case of individuals, the deduction for personal state and local taxes), certain additional limitations on the deduction of net operating losses, certain preferential rates of taxation on certain dividends and certain business income derived by non-corporate taxpayers in comparison to other ordinary income recognized by such taxpayers, and significant changes to the international tax rules. In addition, on August 16, 2022, the Biden administration signed into law the Inflation Reduction Act, which modifies key aspects of the Code, including by creating an alternative minimum tax on certain corporations and an excise tax on stock repurchases by certain corporations. The effect of these and other changes is uncertain, both in terms of the direct effect on the taxation of an investment in the Fund’s shares and their indirect effect on the value of the Fund’s assets, Fund shares or market conditions generally. In addition, the U.S. government has proposed and adopted multiple regulations that could have a long-lasting impact on the Fund and on the closed-end fund industry in general. The SEC’s final rules and amendments that modernize reporting and disclosure, along with other potential upcoming regulations, could, among other things, restrict the Fund’s ability to engage in transactions, and/or increase overall expenses of the Fund. 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(s). | ||||||||||||||||||||||||
| Deflation Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Deflation Risk | ||||||||||||||||||||||||
| Loans Of Portfolio Securities Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Loans of Portfolio Securities Risk The Fund will not lend its portfolio securities if such loans are not permitted by the laws or regulations of any state in which its shares are qualified for sale. The Fund’s loans of portfolio securities will be collateralized in accordance with applicable regulatory requirements, which means that “cash equivalents” accepted as collateral will be limited to securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities or irrevocable letters of credit issued by a bank (other than a borrower of the Fund’s portfolio securities or any affiliate of such borrower) which qualifies as a custodian bank for an investment company under the 1940 Act. The Fund’s ability to lend portfolio securities may be limited by rating agency guidelines (if any). A loan may generally be terminated by the borrower on one business days’ notice, or by the Fund at any time thereby requiring the borrower to redeliver the borrowed securities within the normal and customary settlement time for securities transactions. If the borrower fails to deliver the loaned securities within the normal and customary settlement time for securities transactions, the Fund could use the collateral to replace the securities while holding the borrower liable for any excess of replacement cost over the value of the collateral pledged by the borrower. As with any extensions of credit, there are risks of delay in recovery and in some cases even loss of rights in the collateral should the borrower of the securities violate the terms of the loan or fail financially. However, these loans of portfolio securities will only be made to firms deemed by the Investment Adviser to be creditworthy and when the income which can be earned from such loans justifies the attendant risks. The Board will oversee the creditworthiness of the contracting parties on an ongoing basis. Upon termination of the loan, the borrower is required to return the securities to the Fund. Any gain or loss in the market price during the loan period would inure to the Fund. The risks associated with loans of portfolio securities are substantially similar to those associated with repurchase agreements. Thus, if the counterparty to the loan petitions for bankruptcy or becomes subject to the United States Bankruptcy Code, the law regarding the rights of the Fund is unsettled. As a result, under extreme circumstances, there may be a restriction on the Fund’s ability to sell the collateral and the Fund would suffer a loss. Moreover, because the Fund will re-invest any cash collateral it receives, as described above, the Fund is subject to the risk that the value of the investments it makes will decline and result in losses to the Fund. These losses, in extreme circumstances such as the 2007-2009 financial crisis, could be substantial and have a significant adverse impact on the Fund and its shareholders. When voting or consent rights which accompany loaned securities pass to the borrower, the Fund will follow the policy of calling the loaned securities, to be delivered within one day after notice, to permit the exercise of such rights if the matters involved would have a material effect on the Fund’s investment in such loaned securities. The Fund will pay reasonable finder’s, administrative and custodial fees in connection with a loan of its securities, and may also pay fees to one or more securities lending agents and/or pay other fees or rebates to borrowers. | ||||||||||||||||||||||||
| Investment Dilution Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Investment Dilution Risk | ||||||||||||||||||||||||
| Legal Tax And Regulatory Risks [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Legal, Tax and Regulatory Risks We cannot assure you what percentage of the distributions paid on the Fund’s shares, if any, will consist of tax-advantaged qualified dividend income or long-term capital gains or what the tax rates on various types of income will be in future years. To qualify for the favorable U.S. federal income tax treatment generally accorded to RICs, the Fund must, among other things, meet certain asset diversification tests, 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.” Statutory limitations on distributions on the common shares if the Fund fails to satisfy the 1940 Act’s asset coverage requirements could jeopardize the Fund’s ability to meet such distribution requirements. While the Fund presently intends to purchase or redeem notes or preferred shares, if any, to the extent necessary in order to maintain compliance with such asset coverage requirements, there can be no assurance that such actions can be effected in time to meet the Code requirements. 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 resulting corporate taxes would materially reduce the Fund’s net assets and the amount of cash available for distribution to shareholders. For a more complete discussion of these and other U.S. federal income tax considerations. See “Taxation.” | ||||||||||||||||||||||||
| Nineteen Forty Act Regulation [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | 1940 Act Regulation | ||||||||||||||||||||||||
| Legislation Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Legislation Risk | ||||||||||||||||||||||||
| Reliance On Service Providers Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Reliance on Service Providers Risk | ||||||||||||||||||||||||
| Cyber Security Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Cyber Security Risk of recent highly publicized cases of companies reporting the unauthorized disclosure of client or customer information, as well as cyberattacks involving the dissemination, theft and destruction of corporate information or other assets, as a result of failure to follow procedures by employees or contractors or as a result of actions by third parties, including actions by terrorist organizations and hostile foreign governments. Although service providers typically have policies and procedures, business continuity plans and/or risk management systems intended to identify and mitigate cyber incidents, there are inherent limitations in such plans and systems including the possibility that certain risks have not been identified. Furthermore, the Fund cannot control the cyber security policies, plans and systems put in place by its service providers or any other third parties whose operations may affect the Fund or its shareholders. There can be no assurance that the Fund or its service providers will not suffer losses relating to cyber attacks or other information security breaches in the future. Because technology is consistently changing, new ways to carry out cyber attacks are always developing. Therefore, there is a chance that some risks have not been identified or prepared for, or that an attack may not be detected, which puts limitations on the Fund’s ability to plan for or respond to a cyber attack. In addition to deliberate cyber attacks, unintentional cyber incidents can occur, such as the inadvertent release of confidential information by the Fund or its service providers. Like other funds and business enterprises, the Fund and its service providers are subject to the risk of cyber incidents occurring from time to time. | ||||||||||||||||||||||||
| 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 | ||||||||||||||||||||||||
| Anti Takeover Provisions [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Anti-Takeover Provisions | ||||||||||||||||||||||||
| Dilution Risk [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Dilution Risk Shareholders who do not exercise their subscription rights may, at the completion of such an offering, own a smaller proportional interest in the Fund than if they exercised their subscription rights. As a result of such an offering, a shareholder may experience dilution in net asset value per share if the subscription price per share is below the net asset value per share on the expiration date. If the subscription price per share is below the net asset value per share of the Fund’s shares on the expiration date, a shareholder will experience an immediate dilution of the aggregate net asset value of such shareholder’s shares if the shareholder does not participate in such an offering and the shareholder will experience a reduction in the net asset value per share of such shareholder’s shares whether or not the shareholder participates in such an offering. The Fund cannot state precisely the extent of this dilution (if any) if the shareholder does not exercise such shareholder’s subscription rights because the Fund does not know what the net asset value per share will be when the offer expires or what proportion of the subscription rights will be exercised. | ||||||||||||||||||||||||
| Illiquidity Prior To Exchange Listing [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Illiquidity Prior to Exchange Listing | ||||||||||||||||||||||||
| Market Price Fluctuation [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Market Price Fluctuation | ||||||||||||||||||||||||
| Notes [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | An investment in our notes is subject to special risks. Our notes are not likely to be listed on an exchange or automated quotation system. We cannot assure you that any market will exist for our notes or if a market does exist, whether it will provide holders with liquidity. Broker-dealers that maintain a secondary trading market for the notes are not required to maintain this market, and the Fund is not required to redeem notes if an attempted secondary market sale fails because of a lack of buyers. To the extent that our notes trade, they may trade at a price either higher or lower than their principal amount depending on interest rates, the rating (if any) on such notes and other factors. | ||||||||||||||||||||||||
| Special Risks Of Notes [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Special Risks of Notes to Holders of Preferred Shares As provided in the 1940 Act, and subject to compliance with the Fund’s investment limitations, the Fund may issue notes. In the event the Fund were to issue such securities, the Fund’s obligations to pay dividends or make distributions and, upon liquidation of the Fund, liquidation payments in respect of its preferred shares would be subordinate to the Fund’s obligations to make any principal and interest payments due and owing with respect to its outstanding notes. Accordingly, the Fund’s issuance of notes would have the effect of creating special risks for the Fund’s preferred shareholders that would not be present in a capital structure that did not include such securities. | ||||||||||||||||||||||||
| Common Share Repurchases [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Common Share Repurchases | ||||||||||||||||||||||||
| Common Share Distribution Policy [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Common Share Distribution Policy For the fiscal year ended September 30, 2023, the Fund made distributions of $1.28 per common share, approximately $0.28 per commons share of which constituted a return of capital. The composition of each distribution is estimated based on earnings as of the record date for the distribution. The actual composition of each distribution may change based on the Fund’s investment activity through the end of the calendar year. | ||||||||||||||||||||||||
| Credit Quality Ratings [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | Credit Quality Ratings These guidelines could affect portfolio decisions and may be more stringent than those imposed by the 1940 Act. A rating (if any) by a rating agency does not eliminate or necessarily mitigate the risks of investing in our preferred shares or notes, and a rating may not fully or accurately reflect all of the securities’ credit risks. A rating (if any) does not address liquidity or any other market risks of the securities being rated. A rating agency could downgrade the rating of our notes or preferred shares, which may make such securities less liquid in the secondary market. If a rating agency downgrades the rating assigned to notes or preferred shares, we may alter our portfolio or redeem the preferred securities or notes under certain circumstances. | ||||||||||||||||||||||||
| Subscription Rights [Member] | |||||||||||||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||||||||||||
| Risk [Text Block] | There is a risk that changes in market conditions | ||||||||||||||||||||||||
| [1] If common shares are sold to or through underwriters or dealer managers, a prospectus or prospectus supplement will set forth any applicable sales load and the estimated offering expenses borne by the Fund. “Other Expenses” are estimated based on the Fund’s fiscal year ended September 30, 2023. Based on weekly prices. | |||||||||||||||||||||||||
