| N-2 - USD ($) | 3 Months Ended | 12 Months Ended | |||||||||||||
| Oct. 31, 2024 | Oct. 31, 2024 | Jul. 31, 2024 | Apr. 30, 2024 | Jan. 31, 2024 | Oct. 31, 2023 | Jul. 31, 2023 | Apr. 30, 2023 | Jan. 31, 2023 | Oct. 31, 2022 | Jul. 31, 2022 | Apr. 30, 2022 | Jan. 31, 2022 | Oct. 31, 2024 | ||
| Prospectus [Line Items] | |||||||||||||||
| Document Period End Date | Oct. 31, 2024 | ||||||||||||||
| Cover [Abstract] | |||||||||||||||
| Entity Central Index Key | 0001263994 | ||||||||||||||
| Amendment Flag | false | ||||||||||||||
| Entity Inv Company Type | N-2 | ||||||||||||||
| Document Type | N-CSR | ||||||||||||||
| Entity Registrant Name | Reaves Utility Income Fund | ||||||||||||||
| Fee Table [Abstract] | |||||||||||||||
| Shareholder Transaction Expenses [Table Text Block] | Shareholder Transaction Expenses (as a percentage of offering price) Sales Load (a) – Offering Expenses Borne by Common Shareholders (a) – Dividend Reinvestment Plan Fees (b) None | ||||||||||||||
| Sales Load [Percent] | [1] | 0% | |||||||||||||
| Dividend Reinvestment and Cash Purchase Fees | [2] | $ 0 | |||||||||||||
| Other Transaction Expenses [Abstract] | |||||||||||||||
| Other Transaction Expenses [Percent] | [1] | 0% | |||||||||||||
| Annual Expenses [Table Text Block] | Percentage of Net Assets Annual Expenses Attributable to Common Shares Investment Advisory Fees (c) 0.71% Interest Payments on Borrowed Funds (d) 1.50% Other Expenses (e) 0.22% Acquired Fund Fees & Expenses 0.00% Total Annual Fund Operating Expenses 2.43% | ||||||||||||||
| Management Fees [Percent] | [3] | 0.71% | |||||||||||||
| Interest Expenses on Borrowings [Percent] | [4] | 1.50% | |||||||||||||
| Acquired Fund Fees and Expenses [Percent] | 0% | ||||||||||||||
| Other Annual Expenses [Abstract] | |||||||||||||||
| Other Annual Expenses [Percent] | [5] | 0.22% | |||||||||||||
| Total Annual Expenses [Percent] | 2.43% | ||||||||||||||
| Expense Example [Table Text Block] | Example The purpose of the following table is to help a holder of common shares understand the fees and expenses that such holder would bear directly or indirectly. The following example illustrates the expenses that you would pay on a $1,000 investment in common shares of the Fund assuming (1) that the Fund incurs total annual expenses of 2.43% of its net assets in years 1 through 10 (assuming borrowing equal to 18.50% of the Fund’s total assets) and (2) a 5% annual return. 1 Year 3 Years 5 Years 10 Years $25 $76 $129 $276 The example should not be considered a representation of future expenses or rate of return. The example assumes that all dividends and distributions are reinvested at NAV. The Fund’s actual rate of return may be greater or less than the hypothetical 5% annual return shown in the example. | ||||||||||||||
| Expense Example, Year 01 | $ 25 | ||||||||||||||
| Expense Example, Years 1 to 3 | 76 | ||||||||||||||
| Expense Example, Years 1 to 5 | 129 | ||||||||||||||
| Expense Example, Years 1 to 10 | $ 276 | ||||||||||||||
| Purpose of Fee Table , Note [Text Block] | The following information is intended to assist investors in understanding the fees and expenses (annualized) that an investor in common shares of the Fund would bear, directly or indirectly. The table is based on the capital structure of the Fund for the fiscal year ended October 31, 2024. | ||||||||||||||
| Other Expenses, Note [Text Block] | Other Expenses are estimated based on estimated amounts for the current fiscal year. | ||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Investment Objectives and Practices [Text Block] | Investment Objective There have been no material changes in the Fund’s investment objective since the prior disclosure date that have not been approved by shareholders. The Fund’s investment objective is to provide a high level of after-tax income and total return consisting primarily of tax-advantaged dividend income and capital appreciation. Principal Investment Strategies. There have been no material changes in the Fund’s Principal Investment Strategies and Policies since the prior disclosure date. The Fund pursues its investment objective by investing at least 80% of its total assets in the securities of domestic and foreign companies involved to a significant extent in providing products, services or equipment for (i) the generation or distribution of electricity, gas or water, (ii) telecommunications activities or (iii) infrastructure operations, such as airports, toll roads and municipal services (“Utilities” or the “Utility Industry”). A company will be deemed to be involved in the Utility Industry to a significant extent if at least 50% of its assets, gross income or profits are committed to or derived from activities in the areas described above. The remaining 20% of the Fund’s total assets may be invested in other securities including stocks, debt obligations and money market instruments, as well as certain derivative instruments (described below) and other investments. As used in the Annual Report, as well as the Fund’s Prospectus Supplement and the accompanying Prospectus and Statement of Additional Information, the terms “debt securities” and “debt obligations” refer to bonds, debentures and similar long and intermediate term debt investments and do not include short-term fixed income securities such as money market instruments in which the Fund may invest temporarily pending investment of the proceeds of an offering and during periods of abnormal market conditions. The Fund may invest in preferred stocks and bonds of below investment grade quality (i.e., “junk bonds”). Under normal market conditions, the Fund invests at least 80% of its total assets in dividend-paying common and preferred stocks of companies in the Utility Industry. In pursuing its objective, the Fund invests primarily in common and preferred stocks that pay dividends that qualify for federal income taxation at rates applicable to long-term capital gains (“tax-advantaged dividends”). The Fund may invest in the securities of both domestic and foreign issuers, including those located in emerging market countries (i.e., a country not included in the MSCI World Index, a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets). As an alternative to holding foreign-traded securities, the Fund may invest in dollar-denominated securities of foreign companies that trade on U.S. exchanges or in the U.S. over-the-counter market (including depositary receipts, which evidence ownership in underlying foreign securities). To date, the Fund’s derivatives usage has been limited to equity options, including writing covered calls, the purchase of calls and the sale of puts. Options may be used as both hedges against the value of existing holdings or as speculative trades as part of the Fund’s overall investment strategy. In addition, the Fund may choose to use interest rate swaps (or options thereon) from time to time for hedging purposes. Although the Fund does not currently use interest rate swaps (or options thereon), the Fund may do so in the future, depending on the interest rate outlook of W.H. Reaves & Co., Inc. (dba Reaves Asset Management, the “Adviser”) and other factors. Such usage would be limited to no more than 20% of the Fund’s total assets. The Fund may choose to use other derivatives from time to time, as described in the Statement of Additional Information. There is no assurance that the Fund will achieve its investment objective. Further, the Fund’s ability to pursue its investment objective, the value of the Fund’s investments and the Fund’s NAV may be adversely affected by changes in tax rates and policies. Because the Fund’s investment objective is to provide a high level of after-tax yield and total return consisting primarily of dividend and interest income and capital appreciation, the Fund’s ability to invest, and the attractiveness of investing in, equity securities that pay qualified dividend income in relation to other investment alternatives will be affected by changes in federal income tax laws and regulations, including changes in the qualified dividend income provisions. Any proposed or actual changes in such rates, therefore, can significantly and adversely affect the after-tax returns of the Fund’s investments in equity securities. Any such changes also could significantly and adversely affect the Fund’s NAV, as well as the Fund’s ability to acquire and dispose of equity securities at desirable returns and price levels and the Fund’s ability to pursue its investment objective. The Fund cannot assure you as to the portion, if any, of the Fund’s dividends that will be qualified dividend income Leverage The Fund currently uses leverage through borrowing. More specifically, the Fund has entered into a credit agreement (the “Credit Agreement”) with State Street Bank and Trust Company (the “Bank”). As of October 31, 2024, the Fund had outstanding $650,000,000 in principal amount of borrowings from the Credit Agreement representing approximately 18.50% of the Fund’s total assets (including assets attributable to the Fund’s use of leverage). The Bank has the ability to terminate the Credit Agreement upon 360-days’ notice. The provisions of the 1940 Act further provide that the Fund may borrow or issue notes or debt securities in an amount up to 33 1/3% of its total assets or may issue preferred shares in an amount up to 50% of the Fund’s total assets (including the proceeds from leverage). The Fund has no present intention of issuing preferred shares, although it has done so in the past and may choose to do so in the future. The Fund also may borrow money as a temporary measure for extraordinary or emergency purposes. Leverage creates risks for common shareholders, including the likelihood of greater volatility of NAV and market price of, and dividends paid on, the common shares. There is a risk that fluctuations in the dividend rates on any preferred shares issued by the Fund may adversely affect the return to the common shareholders. If the income from the securities purchased with such funds is not sufficient to cover the cost of leverage, the return on the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced. Changes in the value of the Fund’s portfolio (including investments bought with the proceeds of the leverage program) will be borne entirely by the common shareholders. If there is a net decrease (or increase) in the value of the Fund’s investment portfolio, the leverage will decrease (or increase) the NAV per share to a greater extent than if the Fund were not leveraged. The issuance of a class of preferred shares or incurrence of borrowings having priority over the common shares creates an opportunity for greater return per common share, but at the same time such leveraging is a speculative technique in that it will increase the Fund’s exposure to capital risk. Unless the income and appreciation, if any, on assets acquired with leverage proceeds exceed the associated costs of the leverage program (and other Fund expenses), the use of leverage will diminish the investment performance of the common shares compared with what it would have been without leverage. The fees received by Reaves and certain other service providers are based on the total assets of the Fund, including assets represented by leverage. During periods in which the Fund is using leverage, the fees paid to Reaves for investment advisory services (and separately, to Paralel for administrative services will be higher than if the Fund did not use leverage because the fees paid will be calculated on the basis of the Fund’s total assets, including proceeds from borrowings and the issuance of any preferred shares. Therefore, Reaves may have a financial incentive to use leverage, which creates a conflict of interest between Reaves and common shareholders. Reaves will seek to manage this conflict of interest by utilizing leverage only when they determine such action is in the best interests of the Fund. The Board of Trustees of the Fund (the “Board”) reviews the Fund’s leverage on a periodic basis, and the Fund’s use of leverage may be increased or decreased subject to the Board’s oversight and applicable law. Under the Investment Company Act of 1940, as amended, and the rules and regulations thereunder (the “1940 Act”), the Fund is not permitted to issue preferred shares unless immediately after such issuance the total asset value of the Fund’s portfolio is at least 200% of the liquidation value of the outstanding preferred shares (i.e., such liquidation value may not exceed 50% of the Fund’s total assets). In addition, the Fund is not permitted to declare any cash dividend or other distribution on its common shares unless, at the time of such declaration, the NAV of the Fund’s portfolio (determined after deducting the amount of such dividend or other distribution) is at least 200% of such liquidation value. To qualify for federal income taxation as a “regulated investment company,” the Fund must satisfy certain requirements relating to sources of its income and diversification of its assets, and must distribute in each taxable year at least 90% of its net investment income (including net interest income and net short-term gain). The Fund also will be required to distribute annually substantially all of its income and capital gain, if any, to avoid imposition of a nondeductible 4% federal excise tax. The Fund’s willingness to issue new securities for investment purposes, and the amount the Fund will issue, depends on many factors, the most important of which are market conditions and interest rates. There is no assurance that a leveraging strategy will be successful during any period in which it is employed. The Fund may increase the amount of leverage following the completion of an offering, subject to applicable law. | ||||||||||||||
| Risk Factors [Table Text Block] | Risk Factors Investing in any investment company security involves risk, including the risk that you may receive little or no return on your investment or even that you may lose part or all of your investment. Investors should consider the following risk factors and special considerations associated with investing in the Fund’s common shares: Risks Associated with Offerings of Additional Common Shares Additional Risks of Rights. common shares if the shareholder does not participate in such an offering and the shareholder will experience a reduction in the NAV per share of such shareholder’s common shares whether or not the shareholder participates in such an offering. Such a reduction in NAV per share may have the effect of reducing market price of the common shares. The Fund cannot state precisely the extent of this dilution (if any) if the shareholder does not exercise such shareholder’s Rights because the Fund does not know what the NAV per share will be when the offer expires or what proportion of the Rights will be exercised. If the subscription price is substantially less than the then current NAV per common share at the expiration of a rights offering, such dilution could be substantial. Any such dilution or accretion will depend upon whether (i) such shareholders participate in the rights offering and (ii) the Fund’s NAV per common share is above or below the subscription price on the expiration date of the rights offering. In addition to the economic dilution described above, if a Common Shareholder does not exercise all of their rights, the Common Shareholder will incur voting dilution as a result of this rights offering. This voting dilution will occur because the Common Shareholder will own a smaller proportionate interest in the Fund after the rights offering than prior to the rights offering. There is a risk that changes in market conditions may result in the underlying common shares purchasable upon exercise of the subscription rights being less attractive to investors at the conclusion of the subscription period. This may reduce or eliminate the value of the subscription rights. If investors exercise only a portion of the rights, the number of common shares issued may be reduced, and the common shares may trade at less favorable prices than larger offerings for similar securities. Subscription rights issued by the Fund may be transferable or non-transferable rights. In a non-transferable rights offering, Common Shareholders who do not wish to exercise their rights will be unable to sell their rights. In a transferrable rights offering, the Fund will use its best efforts to ensure an adequate trading market for the rights; however, investors may find that there is no market to sell rights they do not wish to exercise. Investment and Market Risk. Issuer Risk. Income Risk. Leverage Risk. Tax Risk. NAV may be adversely affected by changes in tax rates and policies. Because the Fund’s investment objective is to provide a high level of after-tax yield and total return consisting primarily of dividend and interest income and capital appreciation, the Fund’s ability to invest, and the attractiveness of investing in, equity securities that pay qualified dividend income in relation to other investment alternatives will be affected by changes in federal income tax laws and regulations, including changes in the qualified dividend income provisions. Any proposed or actual changes in such rates, therefore, can significantly and adversely affect the after-tax returns of the Fund’s investments in equity securities. Any such changes also could significantly and adversely affect the Fund’s NAV, as well as the Fund’s ability to acquire and dispose of equity securities at desirable returns and price levels and the Fund’s ability to pursue its investment objective. The Fund cannot assure you as to the portion, if any, of the Fund’s dividends that will be qualified dividend income. Further, in order to avoid corporate income tax at the level of the Fund, it must qualify each year as a regulated investment company under the Code. Sector/Industry Risk. Risks that are intrinsic to utility companies include difficulty in obtaining an adequate return on invested capital, difficulty in financing large construction programs during an inflationary period, restrictions on operations and increased cost and delays attributable to environmental considerations and regulation, difficulty in raising capital in adequate amounts on reasonable terms in periods of high inflation and unsettled capital markets, technological innovations that may render existing plants, equipment or products obsolete, the potential impact of natural or man-made disasters, increased costs and reduced availability of certain types of fuel, occasional reduced availability and high costs of natural gas and other fuels, the effects of energy conservation, the effects of a national energy policy and lengthy delays and greatly increased costs and other problems associated with the design, construction, licensing, regulation and operation of nuclear facilities for electric generation, including, among other considerations, the problems associated with the use of radioactive materials, the disposal of radioactive wastes, shutdown of facilities or release of radiation resulting from catastrophic events, disallowance of costs by regulators which may reduce profitability, and changes in market structure that increase competition. In many regions, including the United States, the Utility Industry is experiencing increasing competitive pressures, primarily in wholesale markets, as a result of consumer demand, technological advances, greater availability of natural gas with respect to electric utility companies and other factors. For example, the Federal Energy Regulatory Commission (the “FERC”) has implemented regulatory changes to increase access to the nationwide transmission grid by utility and non-utility purchasers and sellers of electricity. A number of countries, including the United States, are considering or have implemented methods to introduce and promote retail competition. Changes in regulation may result in consolidation among domestic utilities and the disaggregation of many vertically integrated utilities into separate generation, transmission and distribution businesses. As a result, additional significant competitors could become active in certain parts of the Utility Industry. Due to the high costs of developing, constructing, operating and distributing assets and facilities many utility companies are highly leveraged. As such, movements in the level of interest rates may affect the returns from these assets. See “Risk Factors—Sector/Industry Risk—Interest Rate Risk.” Concentration Risk. Common Stock Risk. Foreign Securities Risk . To the extent the Fund invests in depositary receipts, the Fund will be subject to many of the same risks as when investing directly in non-U.S. securities. The holder of an unsponsored depositary receipt may have limited voting rights and may not receive as much information about the issuer of the underlying securities as would the holder of a sponsored depositary receipt. Foreign Currency Risk. Small and Mid-Cap Stock Risk. Non-Investment Grade Securities Risk. Interest Rate Risk. Credit Risk. Derivatives Risk. judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The Fund may also, from time to time, choose to use interest rate swaps (or options thereon). Derivatives transactions of the types described above subject the Fund to increased risk of principal loss due to imperfect correlation or unexpected price or interest rate movements. The Fund’s use of derivative instruments involves investments risks and transactions costs to which the Fund would not be subject absent the use of these instruments and, accordingly, may result in losses greater than if they had not been used. The Fund also will be subject to credit risk with respect to the counterparties to the over-the-counter derivatives contracts purchased by the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances. As a general matter, dividends received on hedged stock positions are characterized as ordinary income and are not eligible for favorable tax treatment. In addition, use of derivatives may give rise to short-term capital gains and other income that would not qualify for payments by the Fund of tax-advantaged dividends. Preferred Stock Risk. Debt Securities Risk. Inflation Risk. Illiquid Securities Risk. the limited liquidity could affect the market price of the securities, thereby adversely affecting the Fund’s NAV. Market Price of Common Shares. Management Risk. Market Disruption and Geopolitical Risk. Social, political, economic and other conditions and events, such as natural disasters, health emergencies (e.g., epidemics and pandemics), terrorism, wars, conflicts and social unrest, may occur and could significantly impact issuers, industries, governments and other systems, including the financial markets. As global systems, economies and financial markets are increasingly interconnected, events that once had only local impact are now more likely to have regional or even global effects. Events that occur in one country, region or financial market will, more frequently, adversely impact issuers in other countries, regions or markets. These impacts can be exacerbated by failures of governments and societies to adequately respond to an emerging event or threat. These types of events quickly and significantly impact markets in the U.S. and across the globe leading to extreme market volatility and disruption. The extent and nature of the impact on supply chains or economies and markets from these events is unknown. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and generally have a significant impact on the economies and financial markets and the Adviser’s investment advisory activities and services of other service providers, which in turn could adversely affect the Fund’s investments and other operations. The value of the Fund’s investments may decrease as a result of such events, particularly if these events adversely impact the operations and effectiveness of the Adviser or key service providers or if these events disrupt systems and processes necessary or beneficial to the investment advisory or other activities on behalf the Fund. Legislation, Policy and Regulatory Risk. | ||||||||||||||
| Effects of Leverage [Text Block] | Effects of Leverage The following table is furnished in response to requirements of the SEC. It is designed to illustrate the effect of leverage on total return on common shares, assuming investment portfolio total returns (comprised of income, net expenses and changes in the value of investments held in the Fund’s portfolio) of -10%, -5%, 0%, 5% and 10%. These assumed investment portfolio returns are hypothetical figures and are not necessarily indicative of what the Fund’s investment portfolio returns will be. In other words, the Fund’s actual returns may be greater or less than those appearing in the table below. The table further reflects the use of leverage as of October 31, 2024, representing approximately 18.50% of the Fund’s Total Assets and the Fund’s assumed annual leverage interest and fee rate of 5.35%. Assumed Portfolio Return (Net of Expenses) -10.00% -5.00% 0.00% 5.00% 10.00% Corresponding Common Share Total Return -14.64% -8.24% -1.84% 4.57% 10.97% Total return is composed of two elements—the dividends on common shares paid by the Fund (the amount of which is largely determined by the Fund’s net investment income after paying the cost of leverage) and realized and unrealized gains or losses on the value of the securities the Fund owns. As the table shows, leverage generally increases the return to common shareholders when portfolio return is positive or greater than the costs of leverage and decreases return when the portfolio return is negative or less than the costs of leverage. During the time in which the Fund is using leverage, the amount of the fees paid to the Adviser for investment management services is higher than if the Fund did not use leverage because the fees paid are calculated based on the Fund’s Total Assets. This may create a conflict of interest between the Adviser, on the one hand, and common shareholders, on the other. Also, because the leverage costs are borne by the Fund at a specified interest rate, only the Fund’s common shareholders bear the cost of the Fund’s management fees and other expenses. There can be no assurance that a leveraging strategy will be successful during any period in which it is employed. | ||||||||||||||
| Effects of Leverage [Table Text Block] | Assumed Portfolio Return (Net of Expenses) -10.00% -5.00% 0.00% 5.00% 10.00% Corresponding Common Share Total Return -14.64% -8.24% -1.84% 4.57% 10.97% | ||||||||||||||
| Return at Minus Ten [Percent] | (14.64%) | ||||||||||||||
| Return at Minus Five [Percent] | (8.24%) | ||||||||||||||
| Return at Zero [Percent] | (1.84%) | ||||||||||||||
| Return at Plus Five [Percent] | 4.57% | ||||||||||||||
| Return at Plus Ten [Percent] | 10.97% | ||||||||||||||
| Effects of Leverage, Purpose [Text Block] | The following table is furnished in response to requirements of the SEC. It is designed to illustrate the effect of leverage on total return on common shares, assuming investment portfolio total returns (comprised of income, net expenses and changes in the value of investments held in the Fund’s portfolio) of -10%, -5%, 0%, 5% and 10%. These assumed investment portfolio returns are hypothetical figures and are not necessarily indicative of what the Fund’s investment portfolio returns will be. In other words, the Fund’s actual returns may be greater or less than those appearing in the table below. The table further reflects the use of leverage as of October 31, 2024, representing approximately 18.50% of the Fund’s Total Assets and the Fund’s assumed annual leverage interest and fee rate of 5.35%. | ||||||||||||||
| Share Price [Table Text Block] | Market and Net Asset Value Information The common shares are listed on the NYSE American under the symbol “UTG” and began trading on the NYSE American on February 24, 2004. Shares of closed-end investment companies often trade on an exchange at prices lower than NAV. The Fund’s common shares have traded in the market at both premiums to and discounts from NAV. The following table shows, for each fiscal quarter since the quarter ended January 31, 2022; (i) high and low NAVs per common share, (ii) the high and low sale prices per common share, as reported in the consolidated transaction reporting system, and (iii) the percentage by which the common shares traded at a premium over, or discount from, the high and low NAVs per common share. The Fund’s NAV per common share is determined on a daily basis. Market Price Net Asset Value at Market Premium Quarter Low High Market Low Market High Market Low Market High 2024 October $27.95 $33.17 $27.53 $33.34 1.53% 0.33% July 31 $26.11 $28.75 $26.26 $27.97 (0.57)% 2.79% April 30 $25.26 $27.10 $25.14 $26.62 0.48% 1.80% January 31 $24.47 $27.88 $24.87 $27.54 (1.61)% 1.23% 2023 October 31 $23.24 $28.18 $23.38 $27.57 (1.11)% 2.21% July 31 $26.57 $29.07 $26.42 $28.91 0.53% 0.55% Market Price Net Asset Value at Market Premium Quarter Low High Market Low Market High Market Low Market High April 30 $26.32 $30.32 $26.41 $29.96 (3.02)% 1.20% January 31 $27.02 $30.71 $27.45 $30.44 (0.02)% 0.01% 2022 October 31 $24.55 $34.02 $25.10 $33.85 (5.58)% 0.51% July 31 $28.85 $34.50 $28.56 $34.02 1.02% 2.59% April 30 $30.76 $35.43 $30.71 $36.13 (0.65)% (1.94)% January 31 $32.20 $35.44 $31.95 $34.79 (1.08)% 1.90% | ||||||||||||||
| Risks Associated with Offerings of Additional Common Shares [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Risks Associated with Offerings of Additional Common Shares | ||||||||||||||
| Additional Risks of Rights [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Additional Risks of Rights. common shares if the shareholder does not participate in such an offering and the shareholder will experience a reduction in the NAV per share of such shareholder’s common shares whether or not the shareholder participates in such an offering. Such a reduction in NAV per share may have the effect of reducing market price of the common shares. The Fund cannot state precisely the extent of this dilution (if any) if the shareholder does not exercise such shareholder’s Rights because the Fund does not know what the NAV per share will be when the offer expires or what proportion of the Rights will be exercised. If the subscription price is substantially less than the then current NAV per common share at the expiration of a rights offering, such dilution could be substantial. Any such dilution or accretion will depend upon whether (i) such shareholders participate in the rights offering and (ii) the Fund’s NAV per common share is above or below the subscription price on the expiration date of the rights offering. In addition to the economic dilution described above, if a Common Shareholder does not exercise all of their rights, the Common Shareholder will incur voting dilution as a result of this rights offering. This voting dilution will occur because the Common Shareholder will own a smaller proportionate interest in the Fund after the rights offering than prior to the rights offering. There is a risk that changes in market conditions may result in the underlying common shares purchasable upon exercise of the subscription rights being less attractive to investors at the conclusion of the subscription period. This may reduce or eliminate the value of the subscription rights. If investors exercise only a portion of the rights, the number of common shares issued may be reduced, and the common shares may trade at less favorable prices than larger offerings for similar securities. Subscription rights issued by the Fund may be transferable or non-transferable rights. In a non-transferable rights offering, Common Shareholders who do not wish to exercise their rights will be unable to sell their rights. In a transferrable rights offering, the Fund will use its best efforts to ensure an adequate trading market for the rights; however, investors may find that there is no market to sell rights they do not wish to exercise. | ||||||||||||||
| Investment and Market Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Investment and Market Risk. | ||||||||||||||
| Issuer Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Issuer Risk. | ||||||||||||||
| Income Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Income Risk. | ||||||||||||||
| Leverage Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Leverage Risk. | ||||||||||||||
| Tax Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Tax Risk. NAV may be adversely affected by changes in tax rates and policies. Because the Fund’s investment objective is to provide a high level of after-tax yield and total return consisting primarily of dividend and interest income and capital appreciation, the Fund’s ability to invest, and the attractiveness of investing in, equity securities that pay qualified dividend income in relation to other investment alternatives will be affected by changes in federal income tax laws and regulations, including changes in the qualified dividend income provisions. Any proposed or actual changes in such rates, therefore, can significantly and adversely affect the after-tax returns of the Fund’s investments in equity securities. Any such changes also could significantly and adversely affect the Fund’s NAV, as well as the Fund’s ability to acquire and dispose of equity securities at desirable returns and price levels and the Fund’s ability to pursue its investment objective. The Fund cannot assure you as to the portion, if any, of the Fund’s dividends that will be qualified dividend income. Further, in order to avoid corporate income tax at the level of the Fund, it must qualify each year as a regulated investment company under the Code. | ||||||||||||||
| Sector/Industry Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Sector/Industry Risk. Risks that are intrinsic to utility companies include difficulty in obtaining an adequate return on invested capital, difficulty in financing large construction programs during an inflationary period, restrictions on operations and increased cost and delays attributable to environmental considerations and regulation, difficulty in raising capital in adequate amounts on reasonable terms in periods of high inflation and unsettled capital markets, technological innovations that may render existing plants, equipment or products obsolete, the potential impact of natural or man-made disasters, increased costs and reduced availability of certain types of fuel, occasional reduced availability and high costs of natural gas and other fuels, the effects of energy conservation, the effects of a national energy policy and lengthy delays and greatly increased costs and other problems associated with the design, construction, licensing, regulation and operation of nuclear facilities for electric generation, including, among other considerations, the problems associated with the use of radioactive materials, the disposal of radioactive wastes, shutdown of facilities or release of radiation resulting from catastrophic events, disallowance of costs by regulators which may reduce profitability, and changes in market structure that increase competition. In many regions, including the United States, the Utility Industry is experiencing increasing competitive pressures, primarily in wholesale markets, as a result of consumer demand, technological advances, greater availability of natural gas with respect to electric utility companies and other factors. For example, the Federal Energy Regulatory Commission (the “FERC”) has implemented regulatory changes to increase access to the nationwide transmission grid by utility and non-utility purchasers and sellers of electricity. A number of countries, including the United States, are considering or have implemented methods to introduce and promote retail competition. Changes in regulation may result in consolidation among domestic utilities and the disaggregation of many vertically integrated utilities into separate generation, transmission and distribution businesses. As a result, additional significant competitors could become active in certain parts of the Utility Industry. Due to the high costs of developing, constructing, operating and distributing assets and facilities many utility companies are highly leveraged. As such, movements in the level of interest rates may affect the returns from these assets. See “Risk Factors—Sector/Industry Risk—Interest Rate Risk.” | ||||||||||||||
| Concentration Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Concentration Risk. | ||||||||||||||
| Common Stock Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Common Stock Risk. | ||||||||||||||
| Foreign Securities Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Foreign Securities Risk . To the extent the Fund invests in depositary receipts, the Fund will be subject to many of the same risks as when investing directly in non-U.S. securities. The holder of an unsponsored depositary receipt may have limited voting rights and may not receive as much information about the issuer of the underlying securities as would the holder of a sponsored depositary receipt. | ||||||||||||||
| Foreign Currency Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Foreign Currency Risk. | ||||||||||||||
| Small and Mid-Cap Stock Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Small and Mid-Cap Stock Risk. | ||||||||||||||
| Non-Investment Grade Securities Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Non-Investment Grade Securities Risk. | ||||||||||||||
| Credit Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Credit Risk. | ||||||||||||||
| Derivatives Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Derivatives Risk. judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The Fund may also, from time to time, choose to use interest rate swaps (or options thereon). Derivatives transactions of the types described above subject the Fund to increased risk of principal loss due to imperfect correlation or unexpected price or interest rate movements. The Fund’s use of derivative instruments involves investments risks and transactions costs to which the Fund would not be subject absent the use of these instruments and, accordingly, may result in losses greater than if they had not been used. The Fund also will be subject to credit risk with respect to the counterparties to the over-the-counter derivatives contracts purchased by the Fund. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances. As a general matter, dividends received on hedged stock positions are characterized as ordinary income and are not eligible for favorable tax treatment. In addition, use of derivatives may give rise to short-term capital gains and other income that would not qualify for payments by the Fund of tax-advantaged dividends. | ||||||||||||||
| Preferred Stock Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Preferred Stock Risk. | ||||||||||||||
| Debt Securities Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Debt Securities Risk. | ||||||||||||||
| Inflation Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Inflation Risk. | ||||||||||||||
| Illiquid Securities Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Illiquid Securities Risk. the limited liquidity could affect the market price of the securities, thereby adversely affecting the Fund’s NAV. | ||||||||||||||
| Market Price of Common Shares [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Market Price of Common Shares. | ||||||||||||||
| Management Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Management Risk. | ||||||||||||||
| Market Disruption and Geopolitical Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Market Disruption and Geopolitical Risk. Social, political, economic and other conditions and events, such as natural disasters, health emergencies (e.g., epidemics and pandemics), terrorism, wars, conflicts and social unrest, may occur and could significantly impact issuers, industries, governments and other systems, including the financial markets. As global systems, economies and financial markets are increasingly interconnected, events that once had only local impact are now more likely to have regional or even global effects. Events that occur in one country, region or financial market will, more frequently, adversely impact issuers in other countries, regions or markets. These impacts can be exacerbated by failures of governments and societies to adequately respond to an emerging event or threat. These types of events quickly and significantly impact markets in the U.S. and across the globe leading to extreme market volatility and disruption. The extent and nature of the impact on supply chains or economies and markets from these events is unknown. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and generally have a significant impact on the economies and financial markets and the Adviser’s investment advisory activities and services of other service providers, which in turn could adversely affect the Fund’s investments and other operations. The value of the Fund’s investments may decrease as a result of such events, particularly if these events adversely impact the operations and effectiveness of the Adviser or key service providers or if these events disrupt systems and processes necessary or beneficial to the investment advisory or other activities on behalf the Fund. | ||||||||||||||
| Legislation, Policy and Regulatory Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Legislation, Policy and Regulatory Risk. | ||||||||||||||
| Interest Rate Risk [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Risk [Text Block] | Interest Rate Risk. | ||||||||||||||
| Common Shares [Member] | |||||||||||||||
| General Description of Registrant [Abstract] | |||||||||||||||
| Lowest Price or Bid | $ 32.40 | $ 27.95 | $ 26.11 | $ 25.26 | $ 24.47 | $ 23.24 | $ 26.57 | $ 26.32 | $ 27.02 | $ 24.55 | $ 28.85 | $ 30.76 | $ 32.20 | ||
| Highest Price or Bid | $ 32.69 | 33.17 | 28.75 | 27.10 | 27.88 | 28.18 | 29.07 | 30.32 | 30.71 | 34.02 | 34.50 | 35.43 | 35.44 | ||
| Lowest Price or Bid, NAV | 27.53 | 26.26 | 25.14 | 24.87 | 23.38 | 26.42 | 26.41 | 27.45 | 25.10 | 28.56 | 30.71 | 31.95 | |||
| Highest Price or Bid, NAV | $ 33.34 | $ 27.97 | $ 26.62 | $ 27.54 | $ 27.57 | $ 28.91 | $ 29.96 | $ 30.44 | $ 33.85 | $ 34.02 | $ 36.13 | $ 34.79 | |||
| Highest Price or Bid, Premium (Discount) to NAV [Percent] | 0.27% | 0.33% | 2.79% | 1.80% | 1.23% | 2.21% | 0.55% | 1.20% | 0.01% | 0.51% | 2.59% | (1.94%) | 1.90% | ||
| Lowest Price or Bid, Premium (Discount) to NAV [Percent] | (0.61%) | 1.53% | (0.57%) | 0.48% | (1.61%) | (1.11%) | 0.53% | (3.02%) | (0.02%) | (5.58%) | 1.02% | (0.65%) | (1.08%) | ||
| Share Price | $ 32.52 | $ 32.52 | $ 32.52 | ||||||||||||
| NAV Per Share | $ 32.60 | $ 32.60 | $ 32.60 | ||||||||||||
| Latest Premium (Discount) to NAV [Percent] | (0.25%) | ||||||||||||||
| [1]If common shares are sold to or through underwriters, the applicable prospectus supplement will set forth any applicable sales load and the estimated offering expenses borne by the Fund. Under the Fund’s effective registration statement (“Shelf Registration Statement”), as of October 31, 2024, the Fund had commenced an offering of its shares made at-the-market with a maximum sales load paid by investors of 1.00% of the offering price.[2]There will be no brokerage charges with respect to common shares of beneficial interest issued directly by the Fund under the dividend reinvestment plan. You will pay brokerage charges in connection with open market purchases or if you direct the plan agent to sell your common shares held in a dividend reinvestment account.[3]The investment advisory fee is charged as a percentage of the Fund’s average daily total assets.[4]Assumes the use of leverage in the form of borrowing under the Credit Agreement representing 18.50% of the Fund’s total assets as of October 31, 2024 (including any additional leverage obtained through the use of borrowed funds) at an average annual interest rate cost to the Fund of 5.93%.[5] Other Expenses are estimated based on estimated amounts for the current fiscal year. | |||||||||||||||
