BlackRock Enhanced Equity Dividend Trust (BDJ) N-CSR 6 Mar 24 Certified annual shareholder report (management investment company) Financial data

N-2

N-2 - USD ($)		3 Months Ended								12 Months Ended
		Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023
Cover [Abstract]
Entity Central Index Key										0001332283
Amendment Flag										false
Document Type										N-CSR
Entity Registrant Name										BlackRock Enhanced Equity Dividend Trust
Fee Table [Abstract]
Shareholder Transaction Expenses [Table Text Block]										BDJ Shareholder Transaction Expenses Maximum sales load (as a percentage of offering price) (a) 1.00 % Offering expenses borne by the Trust (as a percentage of offering price) (a) 0.01 % $0.02 per share for open market purchases of   Dividend reinvestment plan fees common shares (b) (a) If the common shares are sold to or through underwriters, the Prospectus Supplement will set forth any applicable sales load and the estimated offering expenses. Trust shareholders will pay all offering expenses involved with an offering. (b) Computershare Trust Company, N.A. (the “Reinvestment Plan Agent”) fees for the handling of the reinvestment of dividends will be paid by BDJ. However, shareholders will pay a $0.02 per share fee incurred in connection with open-market purchases, which will be deducted from the value of the dividend. Shareholders will also be charged a $0.02 per share fee if a shareholder directs the Reinvestment Plan Agent to sell the common shares held in a dividend reinvestment account. Per share fees include any applicable brokerage commissions the Reinvestment Plan Agent is required to pay.
Sales Load [Percent]	[1]									1%
Dividend Reinvestment and Cash Purchase Fees	[2]									$ 0.02
Other Transaction Expenses [Abstract]
Other Transaction Expenses [Percent]	[1]									0.01%
Annual Expenses [Table Text Block]										Estimated Annual Expenses Investment advisory fees (c)(d) 0.80 % Other expenses 0.06 Acquired fund fees and expenses (e) 0.01 Total annual expenses (e) 0.87 Fee waivers (d) — Total annual Trust operating expenses after fee waivers (d) 0.87 (c) BDJ currently pays the Manager a monthly fee at an annual contractual investment advisory fee rate of 0.80% of its average weekly value of BDJ’s net assets. (d) BDJ and the Manager have entered into a fee waiver agreement (the “Fee Waiver Agreement”), pursuant to which the Manager has contractually agreed to waive the investment advisory fees with respect to any portion of BDJ’s assets attributable to investments in any equity and fixed-income mutual funds and exchange-traded funds (“ETFs”) managed by the Manager or its affiliates that have a contractual fee, through June 30, 2025. In addition, pursuant to the Fee Waiver Agreement, the Manager has contractually agreed to waive its investment advisory fees by the amount of investment advisory fees BDJ pays to the Manager indirectly through its investment in money market funds managed by the Manager or its affiliates, through June 30, 2025. The Fee Waiver Agreement may be terminated at any time, without the payment of any penalty, only by BDJ (upon the vote of a majority of the Trustees who are not “interested persons” (as defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”), of BDJ (the “Independent Trustees”)) or a majority of the outstanding voting securities of BDJ), upon 90 days’ written notice by BDJ to the Manager. (e) The total annual expenses do not correlate to the ratios to average net assets shown in BDJ’s Financial Highlights for the year ended December 31, 2023, which do not include acquired fund fees and expenses.
Management Fees [Percent]	[2],[3]									0.80%
Acquired Fund Fees and Expenses [Percent]	[4]									0.01%
Other Annual Expenses [Abstract]
Other Annual Expenses [Percent]										0.06%
Total Annual Expenses [Percent]	[4]									0.87%
Waivers and Reimbursements of Fees [Percent]	[3]									0%
Net Expense over Assets [Percent]	[3]									0.87%
Expense Example [Table Text Block]										The following example illustrates BDJ’s expenses (including the sales load of $10.00 and offering costs of $0.15) that shareholders would pay on a $1,000 investment in common shares, assuming (i) total net annual expenses of 0.87% of net assets attributable to common shares and (ii) a 5% annual return: 1 Year 3 Years 5 Years 10 Years Total expenses incurred $ 19 $ 38 $ 58 $ 116
Expense Example, Year 01										$ 19
Expense Example, Years 1 to 3										38
Expense Example, Years 1 to 5										58
Expense Example, Years 1 to 10										$ 116
Purpose of Fee Table , Note [Text Block]										The following table and example are intended to assist shareholders in understanding the various costs and expenses directly or indirectly associated with investing in BDJ’s common shares.
Basis of Transaction Fees, Note [Text Block]										as a percentage of offering price
Other Transaction Fees, Note [Text Block]										Computershare Trust Company, N.A. (the “Reinvestment Plan Agent”) fees for the handling of the reinvestment of dividends will be paid by BDJ. However, shareholders will pay a $0.02 per share fee incurred in connection with open-market purchases, which will be deducted from the value of the dividend. Shareholders will also be charged a $0.02 per share fee if a shareholder directs the Reinvestment Plan Agent to sell the common shares held in a dividend reinvestment account. Per share fees include any applicable brokerage commissions the Reinvestment Plan Agent is required to pay.
Other Expenses, Note [Text Block]										The example should not be considered a representation of future expenses. The example assumes that the estimated “Other expenses” set forth in the Estimated Annual Expenses table are accurate and that all dividends and distributions are reinvested at NAV. Actual expenses may be greater or less than those assumed. BDJ’s actual rate of return may be greater or less than the hypothetical 5% return shown in the example.
Management Fee not based on Net Assets, Note [Text Block]										BDJ and the Manager have entered into a fee waiver agreement (the “Fee Waiver Agreement”), pursuant to which the Manager has contractually agreed to waive the investment advisory fees with respect to any portion of BDJ’s assets attributable to investments in any equity and fixed-income mutual funds and exchange-traded funds (“ETFs”) managed by the Manager or its affiliates that have a contractual fee, through June 30, 2025. In addition, pursuant to the Fee Waiver Agreement, the Manager has contractually agreed to waive its investment advisory fees by the amount of investment advisory fees BDJ pays to the Manager indirectly through its investment in money market funds managed by the Manager or its affiliates, through June 30, 2025. The Fee Waiver Agreement may be terminated at any time, without the payment of any penalty, only by BDJ (upon the vote of a majority of the Trustees who are not “interested persons” (as defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”), of BDJ (the “Independent Trustees”)) or a majority of the outstanding voting securities of BDJ), upon 90 days’ written notice by BDJ to the Manager.
Acquired Fund Total Annual Expenses, Note [Text Block]										The total annual expenses do not correlate to the ratios to average net assets shown in BDJ’s Financial Highlights for the year ended December 31, 2023, which do not include acquired fund fees and expenses.
General Description of Registrant [Abstract]
Risk Factors [Table Text Block]										9. PRINCIPAL RISKS In the normal course of business, the Trusts invest in securities or other instruments and may enter into certain transactions, and such activities subject each Trust to various risks, including among others, fluctuations in the market (market risk) or failure of an issuer to meet all of its obligations. The value of securities or other instruments may also be affected by various factors, including, without limitation: (i) the general economy; (ii) the overall market as well as local, regional or global political and/or social instability; (iii) regulation, taxation or international tax treaties between various countries; or (iv) currency, interest rate and price fluctuations. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues, recessions, or other events could have a significant impact on the Trusts and their investments. BDJ’s, BME’s, BST’s and BUI’s prospectuses provide details of the risks to which each Trust is subject. The Trusts may be exposed to additional risks when reinvesting cash collateral in money market funds that do not seek to maintain a stable NAV per share of $1.00, which may be subject to discretionary liquidity fees under certain circumstances. Illiquidity Risk: Valuation Risk: The price a Trust could receive upon the sale of any particular portfolio investment may differ from a Trust’s valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation technique or a price provided by an independent pricing service. Changes to significant unobservable inputs and assumptions (i.e., publicly traded company multiples, growth rate, time to exit) due to the lack of observable inputs may significantly impact the resulting fair value and therefore a Trust’s results of operations. As a result, the price received upon the sale of an investment may be less than the value ascribed by a Trust, and a Trust could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. A Trust’s ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers. Counterparty Credit Risk: A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract. For OTC options purchased, each Trust bears the risk of loss in the amount of the premiums paid plus the positive change in market values net of any collateral h el With exchange-traded options purchased, there is less counterparty credit risk to the Trusts since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, a Trust does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency). Geographic/Asset Class Risk: As of period end, the Trusts listed below invested a significant portion of their assets in securities in the following sectors: Sectors Trust Name Energy BGR, BCX Financials BDJ Health Care BMEZ, BME Information Technology CII, BSTZ, BST, BIGZ Materials BCX Utilities BUI Changes in economic conditions affecting such sectors would have a greater impact on the Trusts and could affect the value, income and/or liquidity of positions in such securities. Certain Trusts invest a significant portion of their assets in securities within a single or limited number of market sectors. When a fund concentrates its investments in this manner, it assumes the risk that economic, regulatory, political and social conditions affecting such sectors may have a significant impact on the Trust and could affect the income from, or the value or liquidity of, the Trust’s portfolio. Investment percentages in specific sectors are presented in the Schedules of Investments. Certain Trusts invest a substantial amount of their assets in issuers located in a single country or a limited number of countries. When a fund concentrates its investments in this manner, it assumes the risk that economic, regulatory, political and social conditions in those countries may have a significant impact on their investment performance and could affect the income from, or the value or liquidity of, the Trust’s portfolio. Unanticipated or sudden political or social developments may cause uncertainty in the markets and as a result adversely affect the Trust’s investments. Foreign issuers may not be subject to the same uniform accounting, auditing and financial reporting standards and practices as used in the United States. Foreign securities markets may also be more volatile and less liquid than U.S. securities and may be less subject to governmental supervision not typically associated with investing in U.S. securities. Investment percentages in specific countries are presented in the Schedules of Investments. Certain Trusts invest a significant portion of their assets in securities of issuers located in the United States. A decrease in imports or exports, changes in trade regulations, inflation and/or an economic recession in the United States may have a material adverse effect on the U.S. economy and the securities listed on U.S. exchanges. Proposed and adopted policy and legislative changes in the United States may also have a significant effect on U.S. markets generally, as well as on the value of certain securities. Governmental agencies project that the United States will continue to maintain elevated public debt levels for the foreseeable future which may constrain future economic growth. Circumstances could arise that could prevent the timely payment of interest or principal on U.S. government debt, such as reaching the legislative “debt ceiling.” Such non-payment would result in substantial negative consequences for the U.S. economy and the global financial system. If U.S. relations with certain countries deteriorate, it could adversely affect issuers that rely on the United States for trade. The United States has also experienced increased internal unrest and discord. If these trends were to continue, they may have an adverse impact on the U.S. economy and the issuers in which the Trusts invest. Certain Trusts invest a significant portion of their assets in securities of issuers located in Europe or with significant exposure to European issuers or countries. The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns in, or rising government debt levels of, several European countries as well as acts of war in the region. These events may spread to other countries in Europe and may affect the value and liquidity of certain of the Trusts’ investments. Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not work, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world. The United Kingdom has withdrawn from the European Union, and one or more other countries may withdraw from the European Union and/or abandon the Euro, the common currency of the European Union. These events and actions have adversely affected, and may in the future adversely affect, the value and exchange rate of the Euro and may continue to significantly affect the economies of every country in Europe, including countries that do not use the Euro and non-European Union member states. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far reaching. In addition, Russia launched a large-scale invasion of Ukraine on February 24, 2022. The extent and duration of the military action, resulting sanctions and resulting future market disruptions in the region are impossible to predict, but have been, and may continue to be, significant and have a severe adverse effect on the region, including significant negative impacts on the economy and the markets for certain securities and commodities, such as oil and natural gas, as well as other sectors. Risk Factors This section contains a discussion of the general risks of investing in each Trust. The net asset value and market price of, and dividends paid on, the common shares will fluctuate with and be affected by, among other things, the risks more fully described below. As with any fund, there can be no guarantee that a Trust will meet its investment objective or that the Trust’s performance will be positive for any period of time. Each risk noted below is applicable to each Trust unless the specific Trust or Trusts are noted in a parenthetical. The order of the below risk factors does not indicate the significance of any particular risk factor. Non-Diversification Risk (BGR, BIGZ, BMEZ and BCX): Limited Term Risk (BMEZ, BIGZ and BSTZ): Unless the limited term provision of the Trust’s Agreement and Declaration of Trust is amended by shareholders in accordance with the Agreement and Declaration of Trust, or unless the Trust completes an Eligible Tender Offer and converts to perpetual existence, the Trust will dissolve on or about the first business day following the Dissolution Date. The Trust is not a so called “target date” or “life cycle” fund whose asset allocation becomes more conservative over time as its target date, often associated with retirement, approaches. In addition, the Trust is not a “target term” fund and thus does not seek to return its initial public offering price per common share upon dissolution. Trust. The final distribution of net assets upon dissolution may be more than, equal to or less than $20.00 per common share. Because the Trust may adopt a plan of liquidation and make liquidating distributions in advance of the Dissolution Date, the total value of the Trust’s assets returned to common shareholders upon dissolution will be impacted by decisions of the Board and the Manager regarding the timing of adopting a plan of liquidation and making liquidating distributions. This may result in common shareholders receiving liquidating distributions with a value more or less than the value that would have been received if the Trust had liquidated all of its assets on the Dissolution Date, or any other potential date for liquidation, and distributed the proceeds thereof to shareholders. If the Trust conducts an Eligible Tender Offer, the Trust anticipates that funds to pay the aggregate purchase price of shares accepted for purchase pursuant to the tender offer will be first derived from any cash on hand and then from the proceeds from the sale of portfolio investments held by the Trust. The risks related to the disposition of securities in connection with the Trust’s dissolution also would be present in connection with the disposition of securities in connection with an Eligible Tender Offer. It is likely that during the pendency of a tender offer, and possibly for a time thereafter, the Trust will hold a greater than normal percentage of its total assets in cash and cash equivalents, which may impede the Trust’s ability to achieve its investment objectives and decrease returns to shareholders. The tax effect of any such dispositions of portfolio investments will depend on the difference between the price at which the investments are sold and the tax basis of the Trust in the investments. Any capital gains recognized on such dispositions, as reduced by any capital losses the Trust realizes in the year of such dispositions and by any available capital loss carryforwards, will be distributed to shareholders as capital gain dividends (to the extent of net long-term capital gains over net short-term capital losses) or ordinary dividends (to the extent of net short-term capital gains over net long-term capital losses) during or with respect to such year, and such distributions will generally be taxable to common shareholders. If the Trust’s tax basis for the investments sold is less than the sale proceeds, the Trust will recognize capital gains, which the Trust intends to distribute to common shareholders. In addition, the Trust’s purchase of tendered common shares pursuant to an Eligible Tender Offer will have tax consequences for tendering common shareholders and may have tax consequences for non-tendering common shareholders. The purchase of common shares by the Trust pursuant to an Eligible Tender Offer will have the effect of increasing the proportionate interest in the Trust of non-tendering common shareholders. All common shareholders remaining after an Eligible Tender Offer will be subject to any increased risks associated with the reduction in the Trust’s assets resulting from payment for the tendered common shares, such as greater volatility due to decreased diversification and proportionately higher expenses. The reduced assets of the Trust as a result of an Eligible Tender Offer may result in less investment flexibility for the Trust and may have an adverse effect on the Trust’s investment performance. Such reduction in the Trust’s assets may also cause common shares of the Trust to become thinly traded or otherwise negatively impact secondary trading of common shares. A reduction in assets, and the corresponding increase in the Trust’s expense ratio, could result in lower returns and put the Trust at a disadvantage relative to its peers and potentially cause the Trust’s common shares to trade at a wider discount, or smaller premium, to NAV than they otherwise would. Furthermore, the portfolio of the Trust following an Eligible Tender Offer could be significantly different and, therefore, common shareholders retaining an investment in the Trust could be subject to greater risk. For example, the Trust may be required to sell its more liquid, higher quality portfolio investments to purchase common shares that are tendered in an Eligible Tender Offer, which would leave a less liquid, lower quality portfolio for remaining shareholders. The prospects of an Eligible Tender Offer may attract arbitrageurs who would purchase the common shares prior to the tender offer for the sole purpose of tendering those shares which could have the effect of exacerbating the risks described herein for shareholders retaining an investment in the Trust following an Eligible Tender Offer. The Trust is not required to conduct an Eligible Tender Offer. If the Trust conducts an Eligible Tender Offer, there can be no assurance that the payment for tendered common shares would not result in the Trust having aggregate net assets below the Dissolution Threshold, in which case the Eligible Tender Offer will be canceled, no common shares will be repurchased pursuant to the Eligible Tender Offer and the Trust will liquidate on the Dissolution Date (subject to possible extensions). Following the completion of an Eligible Tender Offer in which the payment for tendered common shares would result in the Trust having aggregate net assets greater than or equal to the Dissolution Threshold, the Board may, by a Board Action Vote, eliminate the Dissolution Date without shareholder approval and provide for the Trust’s perpetual existence. Thereafter, the Trust will have a perpetual existence. There is no guarantee that the Board will eliminate the Dissolution Date following the completion of an Eligible Tender Offer so that the Trust will have a perpetual existence. The Manager may have a conflict of interest in recommending to the Board that the Dissolution Date be eliminated and the Trust have a perpetual existence. The Trust is not required to conduct additional tender offers following an Eligible Tender Offer and conversion to perpetual existence. Therefore, remaining common shareholders may not have another opportunity to participate in a tender offer. Shares of closed-end management investment companies frequently trade at a discount from their NAV, and as a result remaining common shareholders may only be able to sell their shares at a discount to NAV. Although it is anticipated that the Trust will have distributed substantially all of its net assets to shareholders as soon as practicable after the Dissolution Date, securities for which no market exists or securities trading at depressed prices, if any, may be placed in a liquidating trust. Securities placed in a liquidating trust may be held for an indefinite period of time, potentially several years or longer, until they can be sold or pay out all of their cash flows. During such time, the shareholders will continue to be exposed to the risks associated with the Trust and the value of their interest in the liquidating trust will fluctuate with the value of the liquidating trust’s remaining assets. Additionally, the tax treatment of the liquidating trust’s assets may differ from the tax treatment applicable to such assets when held by the Trust. To the extent the costs associated with a liquidating trust exceed the value of the remaining securities, the liquidating trust trustees may determine to dispose of the remaining securities in a manner of their choosing. The Trust cannot predict the amount, if any, of securities that will be required to be placed in a liquidating trust or how long it will take to sell or otherwise dispose of such securities. Investment and Market Discount Risk: common Equity Securities Risk: markets Common Stock Risk: nies Small and Mid-Capitalization Company Risk: Preferred Securities Risk: Convertible Securities Risk (BGR, BDJ, BOE, BGY, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI): Warrants Risk (BGR, BOE, BGY, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI): Depositary Receipts Risk (BGR, BOE, BGY, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI): REIT Investment Risk (BDJ, BOE, BGY, BME, BMEZ, BST, BSTZ and BUI): Master Limited Partnerships Risk (BGR, BCX, BST, BSTZ and BUI): Canadian Royalty Trust Risk (BGR, BCX and BUI): Initial Public Offerings (“IPOs”) Risk (BOE, BME, BMEZ, BIGZ, BST and BSTZ): Investments in Unseasoned Companies (BDJ, BOE, BGY, BME, BMEZ, BIGZ, BCX and BSTZ): Dividend-Paying Equity Securities Risk (CII, BDJ, BOE, BGY and BME): The prices of dividend producing equity securities can be highly volatile. Investors should not assume that the Trust’s investments in these securities will necessarily reduce the volatility of the Trust’s NAV or provide “protection,” compared to other types of equity securities, when markets perform poorly. Investment Style Risk: Risks Associated with the Trust’s Options Strategy: • Risks of Writing Options – As the writer of a covered call option, the Trust forgoes, during the option’s life, the opportunity to profit from increases in the market value of the security covering the call option above the sum of the premium and the strike price of the call, but has retained the risk of loss should the price of the underlying security decline. In other words, as the Trust writes covered calls over more of its portfolio, the Trust’s ability to benefit from capital appreciation becomes more limited. If the Trust writes call options on individual securities or index call options that include securities, in each case, that are not in the Trust’s portfolio or that are not in the same proportion as securities in the Trust’s portfolio, the Trust will experience loss, which theoretically could be unlimited, if the value of the individual security, index or basket of securities appreciates above the exercise price of the index option written by the Trust. When the Trust writes put options, it bears the risk of loss if the value of the underlying stock declines below the exercise price minus the put premium. If the option is exercised, the Trust could incur a loss if it is required to purchase the stock underlying the put option at a price greater than the market price of the stock at the time of exercise plus the put premium the Trust received when it wrote the option. While the Trust’s potential gain in writing a put option is limited to the premium received from the purchaser of the put option, the Trust risks a loss equal to the entire exercise price of the option minus the put premium. • Exchange-Listed Options Risks – There can be no assurance that a liquid market will exist when the Trust seeks to close out an exchange-listed option position. Reasons for the absence of a liquid secondary market on an exchange include the following: (i) there may be insufficient trading interest in certain options; (ii) restrictions may be imposed by an exchange on opening transactions or closing transactions or both; (iii) trading halts, suspensions or other restrictions may be imposed with respect to particular classes or series of options; (iv) unusual or unforeseen circumstances may interrupt normal operations on an exchange; (v) the facilities of an exchange or the Options Clearing Corporation (the “OCC”) may not at all times be adequate to handle current trading volume; or (vi) one or more exchanges could, for economic or other reasons, decide or be compelled at some future date to discontinue the trading of options (or a particular class or series of options). • Over-the-Counter Options Risk – The Trust may write (sell) unlisted OTC options. OTC options differ from exchange-listed options in that they are two-party contracts, with exercise price, premium and other terms negotiated between buyer and seller, and generally do not have as much market liquidity as exchange-listed options. The OTC options written by the Trust will not be issued, guaranteed or cleared by the OCC. In addition, the Trust’s ability to terminate OTC options may be more limited than with exchange-traded options. Banks, broker-dealers or other financial institutions participating in such transactions may fail to settle a transaction in accordance with the terms of the option as written. In the event of default or insolvency of the counterparty, the Trust may be unable to liquidate an OTC option position. • Index Options Risk – The Trust may sell index put and call options from time to time. The purchaser of an index put option has the right to any depreciation in the value of the index below the exercise price of the option on or before the expiration date. The purchaser of an index call option has the right to any appreciation in the value of the index over the exercise price of the option on or before the expiration date. Because the exercise of index options is settled in cash, sellers of index call options, such as the Trust, cannot provide in advance for their potential settlement obligations by acquiring and holding the underlying securities. The Trust will lose money if it is required to pay the purchaser of an index option the difference between the cash value of the index on which the option was written and the exercise price and such difference is greater than the premium received by the Trust for writing the option. • Limitation on Options Writing Risk – The number of call options the Trust can write is limited by the total assets the Trust holds. Furthermore, the Trust’s exchange-listed options transactions will be subject to limitations established by each of the exchanges, boards of trade or other trading facilities, if any, on which such options are traded and cleared. • Tax Risk – Income on options on individual stocks will generally not be recognized by the Trust for tax purposes until an option is exercised, lapses or is subject to a “closing transaction” (as defined by applicable regulations) pursuant to which the Trust’s obligations with respect to the option are otherwise terminated. If the option lapses without exercise or is otherwise subject to a closing transaction, the premiums received by the Trust from the writing of such options will generally be characterized as short-term capital gain. If an option written by the Trust is exercised, the Trust may recognize taxable gain depending on the exercise price of the option, the option premium, and the tax basis of the security underlying the option. The character of any gain on the sale of the underlying security as short-term or long-term capital gain will depend on the holding period of the Trust in the underlying security. In general, distributions received by shareholders of the Trust that are attributable to short-term capital gains recognized by the Trust from its options writing activities will be taxed to such shareholders as ordinary income and will not be eligible for the reduced tax rate applicable to qualified dividend income. Index options will generally be “marked-to-market” for U.S. federal income tax purposes. As a result, the Trust will generally recognize gain or loss on the last day of each taxable year equal to the difference between the value of the index option on that date and the adjusted basis of the index option. The adjusted basis of the index option will consequently be increased by such gain or decreased by such loss. Any gain or loss with respect to index options will be treated as short-term capital gain or loss to the extent of 40% of such gain or loss and long-term capital gain or loss to the extent of 60% of such gain or loss. Because the mark-to-market rules may cause the Trust to recognize gain in advance of the receipt of cash, the Trust may be required to dispose of investments in order to meet its U.S. federal income tax distribution requirements. Debt Securities Risk (BGR, BOE, BME, BMEZ, BCX, BST, BSTZ and BUI): • Credit Risk – Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will not be able to make payments of interest and principal when due. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also affect the value of the Trust’s investment in that issuer. The degree of credit risk depends on both the financial condition of the issuer and the terms of the obligation. • Interest Rate Risk – The market value of bonds and other fixed-income securities changes in response to interest rate changes and other factors. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Trust may be subject to a greater risk of rising interest rates due to the recent period of historically low interest rates. For example, if interest rates increase by 1%, assuming a current portfolio duration of ten years, and all other factors being equal, the value of the Trust’s investments would be expected to decrease by 10%. (Duration is a measure of the price sensitivity of a debt security or portfolio of debt securities to relative changes in interest rates.) The magnitude of these fluctuations in the market price of bonds and other fixed-income securities is generally greater for those securities with longer maturities. Fluctuations in the market price of the Trust’s investments will not affect interest income derived from instruments already owned by the Trust, but will be reflected in the Trust’s net asset value. The Trust may lose money if short-term or long-term interest rates rise sharply in a manner not anticipated by Trust management. To the extent the Trust invests in debt securities that may be prepaid at the option of the obligor (such as mortgage-backed securities), the sensitivity of such securities to changes in interest rates may increase (to the detriment of the Trust) 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 Trust 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 fixed-income securities, government-guaranteed securities will fluctuate in value when interest rates change. A general rise in interest rates has the potential to cause investors to move out of fixed-income securities on a large scale, which may increase redemptions from funds that hold large amounts of fixed-income securities. Heavy redemptions could cause the Trust to sell assets at inopportune times or at a loss or depressed value and could hurt the Trust’s performance. • Extension Risk – When interest rates rise, certain obligations will be paid off by the obligor more slowly than anticipated, causing the value of these obligations to fall. • Prepayment Risk – When interest rates fall, certain obligations will be paid off by the obligor more quickly than originally anticipated, and the Trust may have to invest the proceeds in securities with lower yields. High Yield Bonds U.S. Government Obligations Structured Securities Risk (BME, BMEZ, BCX, BST and BSTZ): in interest rates and impact of these factors may cause significant price fluctuations. Additionally, changes in the reference instrument or security may cause the interest rate on the structured security to be reduced to zero. Certain issuers of such structured securities may be deemed to be “investment companies” as defined in the Investment Company Act. As a result, the Trust’s investment in such securities may be limited by certain investment restrictions contained in the Investment Company Act. Derivatives • Leverage Risk – The Trust’s use of derivatives can magnify the Trust’s gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested. • Market Risk – Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Trust could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, the Manager may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Trust’s derivatives positions to lose value. • Counterparty Risk – Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty. • Illiquidity Risk – The possible lack of a liquid secondary market for derivatives and the resulting inability of the Trust to sell or otherwise close a derivatives position could expose the Trust to losses and could make derivatives more difficult for the Trust to value accurately. • Operational Risk – The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error. • Legal Risk – The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract. • Volatility and Correlation Risk – Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Trust’s use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets. • Valuation Risk – Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them. • Hedging Risk – Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Trust’s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences. • Tax Risk – Certain aspects of the tax treatment of derivative instruments, i
Share Price [Table Text Block]										Share Price Data The following tables summarize each Trust’s highest and lowest daily closing market prices on the NYSE per common share, the NAV per common share, and the premium to or discount from NAV, on the date of each of the high and low market prices. The trading volume indicates the number of common shares traded on the NYSE during the respective quarters. NYSE Market Price NAV per Common Premium/ (Discount) on Date of Market Price BDJ — During Quarter Ended High Low High Low High Low Trading Volume December 31, 2023 $  7.91 $  6.92   $ 8.68 $  8.17 (8.87 )% (15.30 )% 38,503,054 September 30, 2023 8.39 7.47 8.96 8.38 (6.36 ) (10.86 ) 35,094,623 June 30, 2023 8.60 8.03 8.76 8.56 (1.83 ) (6.19 ) 24,527,314 March 31, 2023 9.36 8.26 9.15 8.23 2.30 0.36 25,059,984 December 31, 2022 9.50 8.14 9.49 8.58 0.11 (5.13 ) 29,748,145 September 30, 2022 9.71 8.08 9.42 8.47 3.08 (4.60 ) 27,876,699 June 30, 2022 9.96 8.29 10.26 9.26 (2.92 ) (10.48 ) 31,606,667 March 31, 2022 10.43 9.15 10.55 9.73 (1.14 ) (5.96 ) 40,186,783 As of December 31, 2023, BDJ’s market price, NAV per Common Share, and premium/(discount) to NAV per Common Share were $7.69, $8.82, and (12.81)%, respectively.
Capital Stock, Long-Term Debt, and Other Securities [Abstract]
Capital Stock [Table Text Block]										10. CAPITAL SHARE TRANSACTIONS Each Trust is authorized to issue an unlimited number of shares, with the exception of CII, all of which were initially classified as Common Shares. CII is authorized to issue 200 million Common Shares. The par value for each Trust’s Common Shares is $0.001, except for CII, which is $0.10. The Board is authorized, however, to reclassify any unissued Common Shares to Preferred Shares without the approval of Common Shareholders. BDJ, BME, BST and BUI have each filed a prospectus with the SEC allowing them to issue an additional 40,000,000, 4,000,000, 18,000,000 and 8,000,000 Common Shares, respectively, through an equity Shelf Offering. Under the Shelf Offerings, BDJ, BME, BST and BUI, subject to market conditions, may raise additional equity capital from time to time in varying amounts and utilizing various offering methods at a net price at or above each Trust’s NAV per Common Share (calculated within 48 hours of pricing). As of period end, 40,000,000, 3,332,695, 15,898,551 and 7,658,406 Common Shares, respectively, remain available for issuance under the Shelf Offerings. During the year ended December 31, 2023, BDJ, BME, BST and BUI issued 0, 71,333, 1,266,090 and 167,658 shares, respectively, under the Trust’s respective current Shelf Offering and the Trust’s prior Shelf Offering. See Additional Information — Shelf Offering Program for additional information. Initial costs incurred by each of BDJ, BME, BST and BUI in connection with their Shelf Offerings are recorded as “Deferred offering costs” in the Statements of Assets and Liabilities. As shares are sold, a portion of the costs attributable to the shares sold will be charged against paid-in-capital. Any remaining deferred charges at the end of the Shelf Offering period will be charged to expense. For the periods shown, shares issued and outstanding increased by the following amounts as a result of shares issued through the Shelf Offering: Year Ended Trust Name 12/31/23 12/31/22 BME 71,333 774,304 BST 1,266,090 835,359 BUI 167,658 590,894 For the periods shown, shares issued and outstanding increased by the following amounts as a result of dividend reinvestment: Year Ended Trust Name 12/31/23 12/31/22 CII 14,818 — BDJ 78,103 412,658 BME 12,112 38,955 BST 173,563 81,277 BUI 31,913 32,898 The Trusts participate in an open market share repurchase program (the “Repurchase Program”). From December 1, 2022 through November 30, 2023, each Trust may repurchase up to 5% of its outstanding common shares under the Repurchase Program, based on common shares outstanding as of the close of business on November 30, 2022, subject to certain conditions. From December 1, 2023 through November 30, 2024, each Trust may repurchase up to 5% of its outstanding common shares under the Repurchase Program, based on common shares outstanding as of the close of business on November 30, 2023, subject to certain conditions. The Repurchase Program has an accretive effect as shares are purchased at a discount to the Trust’s NAV. There is no assurance that the Trusts will purchase shares in any particular amounts. For the year ended December 31, 2023, CII, BME, BST and BUI did not repurchase any shares. The total cost of the shares repurchased is reflected in the Trusts’ Statements of Changes in Net Assets. For the periods shown, shares repurchased and cost, including transaction costs, were as follows:   BGR Shares Amounts Year Ended December 31, 2023 587,768 $ 7,413,692 Year Ended December 31, 2022 1,055,728 12,296,655 BDJ Shares Amounts Year Ended December 31, 2023 359,086 $ 2,735,878 BOE Shares Amounts Year Ended December 31, 2023 1,214,010 $ 11,889,663 Year Ended December 31, 2022 1,285,502 12,470,648 BGY Shares Amounts Year Ended December 31, 2023 2,473,793 $ 13,143,239 Year Ended December 31, 2022 1,492,331 7,282,700 BMEZ Shares Amounts Year Ended December 31, 2023 3,082,831 $ 47,918,763 Year Ended December 31, 2022 3,072,736 47,829,587 BIGZ Shares Amounts Year Ended December 31, 2023 5,247,265 $  37,872,639 Year Ended December 31, 2022 8,519,618 64,919,571   BCX Shares Amounts Year Ended December 31, 2023 3,155,189 $  29,812,008 Year Ended December 31, 2022 797,510 7,554,830 BSTZ Shares Amounts Year Ended December 31, 2023 2,006,073 $  34,325,597 Year Ended December 31, 2022 461,288 7,293,625 For the year ended December 31, 2022, shares issued and outstanding remained constant for CII. As of December 31, 2023, BlackRock Financial Management, Inc., an affiliate of the Trust, owned 5,000 Shares of BIGZ.
Outstanding Securities [Table Text Block]										BDJ, BME, BST and BUI have each filed a prospectus with the SEC allowing them to issue an additional 40,000,000, 4,000,000, 18,000,000 and 8,000,000 Common Shares, respectively, through an equity Shelf Offering.
Illiquidity Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Illiquidity Risk:
Valuation Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Valuation Risk: The price a Trust could receive upon the sale of any particular portfolio investment may differ from a Trust’s valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation technique or a price provided by an independent pricing service. Changes to significant unobservable inputs and assumptions (i.e., publicly traded company multiples, growth rate, time to exit) due to the lack of observable inputs may significantly impact the resulting fair value and therefore a Trust’s results of operations. As a result, the price received upon the sale of an investment may be less than the value ascribed by a Trust, and a Trust could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. A Trust’s ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers.
Counterparty Credit Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Counterparty Credit Risk: A derivative contract may suffer a mark-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform under the contract. For OTC options purchased, each Trust bears the risk of loss in the amount of the premiums paid plus the positive change in market values net of any collateral h el With exchange-traded options purchased, there is less counterparty credit risk to the Trusts since the exchange or clearinghouse, as counterparty to such instruments, guarantees against a possible default. The clearinghouse stands between the buyer and the seller of the contract; therefore, credit risk is limited to failure of the clearinghouse. While offset rights may exist under applicable law, a Trust does not have a contractual right of offset against a clearing broker or clearinghouse in the event of a default (including the bankruptcy or insolvency).
GeographicAsset Class Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Geographic/Asset Class Risk: As of period end, the Trusts listed below invested a significant portion of their assets in securities in the following sectors: Sectors Trust Name Energy BGR, BCX Financials BDJ Health Care BMEZ, BME Information Technology CII, BSTZ, BST, BIGZ Materials BCX Utilities BUI Changes in economic conditions affecting such sectors would have a greater impact on the Trusts and could affect the value, income and/or liquidity of positions in such securities. Certain Trusts invest a significant portion of their assets in securities within a single or limited number of market sectors. When a fund concentrates its investments in this manner, it assumes the risk that economic, regulatory, political and social conditions affecting such sectors may have a significant impact on the Trust and could affect the income from, or the value or liquidity of, the Trust’s portfolio. Investment percentages in specific sectors are presented in the Schedules of Investments. Certain Trusts invest a substantial amount of their assets in issuers located in a single country or a limited number of countries. When a fund concentrates its investments in this manner, it assumes the risk that economic, regulatory, political and social conditions in those countries may have a significant impact on their investment performance and could affect the income from, or the value or liquidity of, the Trust’s portfolio. Unanticipated or sudden political or social developments may cause uncertainty in the markets and as a result adversely affect the Trust’s investments. Foreign issuers may not be subject to the same uniform accounting, auditing and financial reporting standards and practices as used in the United States. Foreign securities markets may also be more volatile and less liquid than U.S. securities and may be less subject to governmental supervision not typically associated with investing in U.S. securities. Investment percentages in specific countries are presented in the Schedules of Investments. Certain Trusts invest a significant portion of their assets in securities of issuers located in the United States. A decrease in imports or exports, changes in trade regulations, inflation and/or an economic recession in the United States may have a material adverse effect on the U.S. economy and the securities listed on U.S. exchanges. Proposed and adopted policy and legislative changes in the United States may also have a significant effect on U.S. markets generally, as well as on the value of certain securities. Governmental agencies project that the United States will continue to maintain elevated public debt levels for the foreseeable future which may constrain future economic growth. Circumstances could arise that could prevent the timely payment of interest or principal on U.S. government debt, such as reaching the legislative “debt ceiling.” Such non-payment would result in substantial negative consequences for the U.S. economy and the global financial system. If U.S. relations with certain countries deteriorate, it could adversely affect issuers that rely on the United States for trade. The United States has also experienced increased internal unrest and discord. If these trends were to continue, they may have an adverse impact on the U.S. economy and the issuers in which the Trusts invest. Certain Trusts invest a significant portion of their assets in securities of issuers located in Europe or with significant exposure to European issuers or countries. The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns in, or rising government debt levels of, several European countries as well as acts of war in the region. These events may spread to other countries in Europe and may affect the value and liquidity of certain of the Trusts’ investments. Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not work, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world. The United Kingdom has withdrawn from the European Union, and one or more other countries may withdraw from the European Union and/or abandon the Euro, the common currency of the European Union. These events and actions have adversely affected, and may in the future adversely affect, the value and exchange rate of the Euro and may continue to significantly affect the economies of every country in Europe, including countries that do not use the Euro and non-European Union member states. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far reaching. In addition, Russia launched a large-scale invasion of Ukraine on February 24, 2022. The extent and duration of the military action, resulting sanctions and resulting future market disruptions in the region are impossible to predict, but have been, and may continue to be, significant and have a severe adverse effect on the region, including significant negative impacts on the economy and the markets for certain securities and commodities, such as oil and natural gas, as well as other sectors.
Non Diversification Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Non-Diversification Risk (BGR, BIGZ, BMEZ and BCX):
Limited Term Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Limited Term Risk (BMEZ, BIGZ and BSTZ): Unless the limited term provision of the Trust’s Agreement and Declaration of Trust is amended by shareholders in accordance with the Agreement and Declaration of Trust, or unless the Trust completes an Eligible Tender Offer and converts to perpetual existence, the Trust will dissolve on or about the first business day following the Dissolution Date. The Trust is not a so called “target date” or “life cycle” fund whose asset allocation becomes more conservative over time as its target date, often associated with retirement, approaches. In addition, the Trust is not a “target term” fund and thus does not seek to return its initial public offering price per common share upon dissolution. Trust. The final distribution of net assets upon dissolution may be more than, equal to or less than $20.00 per common share. Because the Trust may adopt a plan of liquidation and make liquidating distributions in advance of the Dissolution Date, the total value of the Trust’s assets returned to common shareholders upon dissolution will be impacted by decisions of the Board and the Manager regarding the timing of adopting a plan of liquidation and making liquidating distributions. This may result in common shareholders receiving liquidating distributions with a value more or less than the value that would have been received if the Trust had liquidated all of its assets on the Dissolution Date, or any other potential date for liquidation, and distributed the proceeds thereof to shareholders. If the Trust conducts an Eligible Tender Offer, the Trust anticipates that funds to pay the aggregate purchase price of shares accepted for purchase pursuant to the tender offer will be first derived from any cash on hand and then from the proceeds from the sale of portfolio investments held by the Trust. The risks related to the disposition of securities in connection with the Trust’s dissolution also would be present in connection with the disposition of securities in connection with an Eligible Tender Offer. It is likely that during the pendency of a tender offer, and possibly for a time thereafter, the Trust will hold a greater than normal percentage of its total assets in cash and cash equivalents, which may impede the Trust’s ability to achieve its investment objectives and decrease returns to shareholders. The tax effect of any such dispositions of portfolio investments will depend on the difference between the price at which the investments are sold and the tax basis of the Trust in the investments. Any capital gains recognized on such dispositions, as reduced by any capital losses the Trust realizes in the year of such dispositions and by any available capital loss carryforwards, will be distributed to shareholders as capital gain dividends (to the extent of net long-term capital gains over net short-term capital losses) or ordinary dividends (to the extent of net short-term capital gains over net long-term capital losses) during or with respect to such year, and such distributions will generally be taxable to common shareholders. If the Trust’s tax basis for the investments sold is less than the sale proceeds, the Trust will recognize capital gains, which the Trust intends to distribute to common shareholders. In addition, the Trust’s purchase of tendered common shares pursuant to an Eligible Tender Offer will have tax consequences for tendering common shareholders and may have tax consequences for non-tendering common shareholders. The purchase of common shares by the Trust pursuant to an Eligible Tender Offer will have the effect of increasing the proportionate interest in the Trust of non-tendering common shareholders. All common shareholders remaining after an Eligible Tender Offer will be subject to any increased risks associated with the reduction in the Trust’s assets resulting from payment for the tendered common shares, such as greater volatility due to decreased diversification and proportionately higher expenses. The reduced assets of the Trust as a result of an Eligible Tender Offer may result in less investment flexibility for the Trust and may have an adverse effect on the Trust’s investment performance. Such reduction in the Trust’s assets may also cause common shares of the Trust to become thinly traded or otherwise negatively impact secondary trading of common shares. A reduction in assets, and the corresponding increase in the Trust’s expense ratio, could result in lower returns and put the Trust at a disadvantage relative to its peers and potentially cause the Trust’s common shares to trade at a wider discount, or smaller premium, to NAV than they otherwise would. Furthermore, the portfolio of the Trust following an Eligible Tender Offer could be significantly different and, therefore, common shareholders retaining an investment in the Trust could be subject to greater risk. For example, the Trust may be required to sell its more liquid, higher quality portfolio investments to purchase common shares that are tendered in an Eligible Tender Offer, which would leave a less liquid, lower quality portfolio for remaining shareholders. The prospects of an Eligible Tender Offer may attract arbitrageurs who would purchase the common shares prior to the tender offer for the sole purpose of tendering those shares which could have the effect of exacerbating the risks described herein for shareholders retaining an investment in the Trust following an Eligible Tender Offer. The Trust is not required to conduct an Eligible Tender Offer. If the Trust conducts an Eligible Tender Offer, there can be no assurance that the payment for tendered common shares would not result in the Trust having aggregate net assets below the Dissolution Threshold, in which case the Eligible Tender Offer will be canceled, no common shares will be repurchased pursuant to the Eligible Tender Offer and the Trust will liquidate on the Dissolution Date (subject to possible extensions). Following the completion of an Eligible Tender Offer in which the payment for tendered common shares would result in the Trust having aggregate net assets greater than or equal to the Dissolution Threshold, the Board may, by a Board Action Vote, eliminate the Dissolution Date without shareholder approval and provide for the Trust’s perpetual existence. Thereafter, the Trust will have a perpetual existence. There is no guarantee that the Board will eliminate the Dissolution Date following the completion of an Eligible Tender Offer so that the Trust will have a perpetual existence. The Manager may have a conflict of interest in recommending to the Board that the Dissolution Date be eliminated and the Trust have a perpetual existence. The Trust is not required to conduct additional tender offers following an Eligible Tender Offer and conversion to perpetual existence. Therefore, remaining common shareholders may not have another opportunity to participate in a tender offer. Shares of closed-end management investment companies frequently trade at a discount from their NAV, and as a result remaining common shareholders may only be able to sell their shares at a discount to NAV. Although it is anticipated that the Trust will have distributed substantially all of its net assets to shareholders as soon as practicable after the Dissolution Date, securities for which no market exists or securities trading at depressed prices, if any, may be placed in a liquidating trust. Securities placed in a liquidating trust may be held for an indefinite period of time, potentially several years or longer, until they can be sold or pay out all of their cash flows. During such time, the shareholders will continue to be exposed to the risks associated with the Trust and the value of their interest in the liquidating trust will fluctuate with the value of the liquidating trust’s remaining assets. Additionally, the tax treatment of the liquidating trust’s assets may differ from the tax treatment applicable to such assets when held by the Trust. To the extent the costs associated with a liquidating trust exceed the value of the remaining securities, the liquidating trust trustees may determine to dispose of the remaining securities in a manner of their choosing. The Trust cannot predict the amount, if any, of securities that will be required to be placed in a liquidating trust or how long it will take to sell or otherwise dispose of such securities.
Investment and Market Discount Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Investment and Market Discount Risk: common
Equity Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Equity Securities Risk: markets
Common Stock Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Common Stock Risk: nies
Small and Mid Capitalization Company Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Small and Mid-Capitalization Company Risk:
Preferred Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Preferred Securities Risk:
Convertible Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Convertible Securities Risk (BGR, BDJ, BOE, BGY, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI):
Warrants Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Warrants Risk (BGR, BOE, BGY, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI):
Depositary Receipts Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Depositary Receipts Risk (BGR, BOE, BGY, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI):
REIT Investment Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										REIT Investment Risk (BDJ, BOE, BGY, BME, BMEZ, BST, BSTZ and BUI):
Master Limited Partnerships Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Master Limited Partnerships Risk (BGR, BCX, BST, BSTZ and BUI):
Canadian Royalty Trust Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Canadian Royalty Trust Risk (BGR, BCX and BUI):
Initial Public Offerings IPOs Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Initial Public Offerings (“IPOs”) Risk (BOE, BME, BMEZ, BIGZ, BST and BSTZ):
Investments in Unseasoned Companies [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Investments in Unseasoned Companies (BDJ, BOE, BGY, BME, BMEZ, BIGZ, BCX and BSTZ):
Dividend Paying Equity Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Dividend-Paying Equity Securities Risk (CII, BDJ, BOE, BGY and BME): The prices of dividend producing equity securities can be highly volatile. Investors should not assume that the Trust’s investments in these securities will necessarily reduce the volatility of the Trust’s NAV or provide “protection,” compared to other types of equity securities, when markets perform poorly.
Investment Style Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Investment Style Risk:
Risks Associated with the Trusts Options Strategy [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Risks Associated with the Trust’s Options Strategy: • Risks of Writing Options – As the writer of a covered call option, the Trust forgoes, during the option’s life, the opportunity to profit from increases in the market value of the security covering the call option above the sum of the premium and the strike price of the call, but has retained the risk of loss should the price of the underlying security decline. In other words, as the Trust writes covered calls over more of its portfolio, the Trust’s ability to benefit from capital appreciation becomes more limited. If the Trust writes call options on individual securities or index call options that include securities, in each case, that are not in the Trust’s portfolio or that are not in the same proportion as securities in the Trust’s portfolio, the Trust will experience loss, which theoretically could be unlimited, if the value of the individual security, index or basket of securities appreciates above the exercise price of the index option written by the Trust. When the Trust writes put options, it bears the risk of loss if the value of the underlying stock declines below the exercise price minus the put premium. If the option is exercised, the Trust could incur a loss if it is required to purchase the stock underlying the put option at a price greater than the market price of the stock at the time of exercise plus the put premium the Trust received when it wrote the option. While the Trust’s potential gain in writing a put option is limited to the premium received from the purchaser of the put option, the Trust risks a loss equal to the entire exercise price of the option minus the put premium. • Exchange-Listed Options Risks – There can be no assurance that a liquid market will exist when the Trust seeks to close out an exchange-listed option position. Reasons for the absence of a liquid secondary market on an exchange include the following: (i) there may be insufficient trading interest in certain options; (ii) restrictions may be imposed by an exchange on opening transactions or closing transactions or both; (iii) trading halts, suspensions or other restrictions may be imposed with respect to particular classes or series of options; (iv) unusual or unforeseen circumstances may interrupt normal operations on an exchange; (v) the facilities of an exchange or the Options Clearing Corporation (the “OCC”) may not at all times be adequate to handle current trading volume; or (vi) one or more exchanges could, for economic or other reasons, decide or be compelled at some future date to discontinue the trading of options (or a particular class or series of options). • Over-the-Counter Options Risk – The Trust may write (sell) unlisted OTC options. OTC options differ from exchange-listed options in that they are two-party contracts, with exercise price, premium and other terms negotiated between buyer and seller, and generally do not have as much market liquidity as exchange-listed options. The OTC options written by the Trust will not be issued, guaranteed or cleared by the OCC. In addition, the Trust’s ability to terminate OTC options may be more limited than with exchange-traded options. Banks, broker-dealers or other financial institutions participating in such transactions may fail to settle a transaction in accordance with the terms of the option as written. In the event of default or insolvency of the counterparty, the Trust may be unable to liquidate an OTC option position. • Index Options Risk – The Trust may sell index put and call options from time to time. The purchaser of an index put option has the right to any depreciation in the value of the index below the exercise price of the option on or before the expiration date. The purchaser of an index call option has the right to any appreciation in the value of the index over the exercise price of the option on or before the expiration date. Because the exercise of index options is settled in cash, sellers of index call options, such as the Trust, cannot provide in advance for their potential settlement obligations by acquiring and holding the underlying securities. The Trust will lose money if it is required to pay the purchaser of an index option the difference between the cash value of the index on which the option was written and the exercise price and such difference is greater than the premium received by the Trust for writing the option. • Limitation on Options Writing Risk – The number of call options the Trust can write is limited by the total assets the Trust holds. Furthermore, the Trust’s exchange-listed options transactions will be subject to limitations established by each of the exchanges, boards of trade or other trading facilities, if any, on which such options are traded and cleared. • Tax Risk – Income on options on individual stocks will generally not be recognized by the Trust for tax purposes until an option is exercised, lapses or is subject to a “closing transaction” (as defined by applicable regulations) pursuant to which the Trust’s obligations with respect to the option are otherwise terminated. If the option lapses without exercise or is otherwise subject to a closing transaction, the premiums received by the Trust from the writing of such options will generally be characterized as short-term capital gain. If an option written by the Trust is exercised, the Trust may recognize taxable gain depending on the exercise price of the option, the option premium, and the tax basis of the security underlying the option. The character of any gain on the sale of the underlying security as short-term or long-term capital gain will depend on the holding period of the Trust in the underlying security. In general, distributions received by shareholders of the Trust that are attributable to short-term capital gains recognized by the Trust from its options writing activities will be taxed to such shareholders as ordinary income and will not be eligible for the reduced tax rate applicable to qualified dividend income. Index options will generally be “marked-to-market” for U.S. federal income tax purposes. As a result, the Trust will generally recognize gain or loss on the last day of each taxable year equal to the difference between the value of the index option on that date and the adjusted basis of the index option. The adjusted basis of the index option will consequently be increased by such gain or decreased by such loss. Any gain or loss with respect to index options will be treated as short-term capital gain or loss to the extent of 40% of such gain or loss and long-term capital gain or loss to the extent of 60% of such gain or loss. Because the mark-to-market rules may cause the Trust to recognize gain in advance of the receipt of cash, the Trust may be required to dispose of investments in order to meet its U.S. federal income tax distribution requirements.
Debt Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Debt Securities Risk (BGR, BOE, BME, BMEZ, BCX, BST, BSTZ and BUI): • Credit Risk – Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will not be able to make payments of interest and principal when due. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also affect the value of the Trust’s investment in that issuer. The degree of credit risk depends on both the financial condition of the issuer and the terms of the obligation. • Interest Rate Risk – The market value of bonds and other fixed-income securities changes in response to interest rate changes and other factors. Interest rate risk is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Trust may be subject to a greater risk of rising interest rates due to the recent period of historically low interest rates. For example, if interest rates increase by 1%, assuming a current portfolio duration of ten years, and all other factors being equal, the value of the Trust’s investments would be expected to decrease by 10%. (Duration is a measure of the price sensitivity of a debt security or portfolio of debt securities to relative changes in interest rates.) The magnitude of these fluctuations in the market price of bonds and other fixed-income securities is generally greater for those securities with longer maturities. Fluctuations in the market price of the Trust’s investments will not affect interest income derived from instruments already owned by the Trust, but will be reflected in the Trust’s net asset value. The Trust may lose money if short-term or long-term interest rates rise sharply in a manner not anticipated by Trust management. To the extent the Trust invests in debt securities that may be prepaid at the option of the obligor (such as mortgage-backed securities), the sensitivity of such securities to changes in interest rates may increase (to the detriment of the Trust) 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 Trust 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 fixed-income securities, government-guaranteed securities will fluctuate in value when interest rates change. A general rise in interest rates has the potential to cause investors to move out of fixed-income securities on a large scale, which may increase redemptions from funds that hold large amounts of fixed-income securities. Heavy redemptions could cause the Trust to sell assets at inopportune times or at a loss or depressed value and could hurt the Trust’s performance. • Extension Risk – When interest rates rise, certain obligations will be paid off by the obligor more slowly than anticipated, causing the value of these obligations to fall. • Prepayment Risk – When interest rates fall, certain obligations will be paid off by the obligor more quickly than originally anticipated, and the Trust may have to invest the proceeds in securities with lower yields.
High Yield Bonds Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										High Yield Bonds
U S Government Obligations Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										U.S. Government Obligations
Structured Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Structured Securities Risk (BME, BMEZ, BCX, BST and BSTZ): in interest rates and impact of these factors may cause significant price fluctuations. Additionally, changes in the reference instrument or security may cause the interest rate on the structured security to be reduced to zero. Certain issuers of such structured securities may be deemed to be “investment companies” as defined in the Investment Company Act. As a result, the Trust’s investment in such securities may be limited by certain investment restrictions contained in the Investment Company Act.
Derivatives Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Derivatives • Leverage Risk – The Trust’s use of derivatives can magnify the Trust’s gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested. • Market Risk – Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Trust could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, the Manager may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Trust’s derivatives positions to lose value. • Counterparty Risk – Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty. • Illiquidity Risk – The possible lack of a liquid secondary market for derivatives and the resulting inability of the Trust to sell or otherwise close a derivatives position could expose the Trust to losses and could make derivatives more difficult for the Trust to value accurately. • Operational Risk – The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error. • Legal Risk – The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract. • Volatility and Correlation Risk – Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Trust’s use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets. • Valuation Risk – Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them. • Hedging Risk – Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Trust’s hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences. • Tax Risk – Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority. Such treatment may be less favorable than that given to a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Trust realizes from its investments.
Foreign Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Foreign Securities Risk: • The Trust generally holds its foreign securities and cash in foreign banks and securities depositories, which may be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory oversight. • Changes in foreign currency exchange rates can affect the value of the Trust’s portfolio. • The economies of certain foreign markets may not compare favorably with the economy of the United States with respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of payments position. • The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer currency, securities, derivatives or other assets. • Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as does the United States and may not have laws to protect investors that are comparable to U.S. securities laws. • Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of securities not typically associated with settlement and clearance of U.S. investments. • The Trust’s claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the foreign country, accruals in the Trust’s net asset value for such refunds may be written down partially or in full, which will adversely affect the Trust’s net asset value. • The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns in, or rising government debt levels of, several European countries as well as acts of war in the region. These events may spread to other countries in Europe and may affect the value and liquidity of certain of the Trust’s investments.
Foreign Currency Transactions Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Foreign Currency Transactions Risk (BGR, BDJ, BME and BCX):
Emerging Markets Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Emerging Markets Risk:
Concentration Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Concentration Risk (BGR, BME, BMEZ, BCX, BST and BSTZ):
Science and Technology Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Science and Technology Risk (BST and BSTZ):
Health Sciences and Healthcare Companies Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Health Sciences and Healthcare Companies Risk (BME and BMEZ):
Energy Sector Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Energy Sector Risk (BGR):
Energy and Natural Resources Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Energy and Natural Resources Risk (BCX):
Commodities Related Investments Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Commodities Related Investments Risk (BCX):
Commodities Market Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Commodities Market Risk (BCX):
Risks of Investing in Utilities Infrastructure and Power Opportunities Issuers [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Risks of Investing in Utilities, Infrastructure and Power Opportunities Issuers (BUI): • Utilities Companies Risk – A variety of factors may adversely affect the business or operations of Utilities issuers, including, but not limited to: high interest costs in connection with capital construction and improvement programs; governmental regulation of rates charged to customers (including the potential that costs incurred by the utility change more rapidly than the rate the utility is permitted to charge its customers); costs associated with compliance with and changes in environmental and other regulations; effects of economic slowdowns and surplus capacity; increased competition from other providers of utility services; inexperience with and potential losses resulting from a developing deregulatory environment; costs associated with reduced availability of certain types of fuel; the effects of energy conservation policies; effects of a national energy policy; technological innovations; potential impact of terrorist activities; the impact of natural or man-made disasters; regulation by various governmental authorities, including the imposition of special tariffs; and changes in tax laws, regulatory policies and accounting standards. • Infrastructure Companies Risk – Infrastructure issuers may be susceptible to a variety of factors that may adversely affect their business and operations, including, but not limited to: high interest costs in connection with capital construction programs; high leverage; costs associated with environmental and other regulations; surplus capacity costs; and reduced investment in public and private infrastructure projects. A slowdown in new infrastructure projects in developing or developed markets may constrain the abilities of Infrastructure issuers to grow in global markets. Other developments, such as significant changes in population levels or changes in the urbanization and industrialization of developing countries, may reduce demand for products or services provided by Infrastructure issuers. • Power Opportunities Companies Risk – A variety of factors may adversely affect the business or operations of Power Opportunities issuers, including, but not limited to: research and development costs related to new technologies; the success or failure of efforts to develop or implement new or existing technologies; government regulation (including environmental regulation); world events and economic conditions, the cyclical nature of the energy sector; intense competition; events relating to domestic and international political developments; energy conservation; environmental costs and liabilities; and the success of exploration projects.
Innovative Securities Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Innovative Securities
Supply and Demand Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Supply and Demand Risk (BGR):
Depletion and Exploration Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Depletion and Exploration Risk (BGR):
Commodity Pricing Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Commodity Pricing Risk (BGR):
Leverage Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Leverage Risk: The use of leverage creates an opportunity for increased common share net investment income dividends, but also creates risks for the holders of common shares. The Trust cannot assure you that the use of leverage will result in a higher yield on the common shares. Any leveraging strategy the Trust employs may not be successful. Leverage involves risks and special considerations for common shareholders, including: • the likelihood of greater volatility of net asset value, market price and dividend rate of the common shares than a comparable portfolio without leverage; • the risk that fluctuations in interest rates or dividend rates on any leverage that the Trust must pay will reduce the return to the common shareholders; • the effect of leverage in a declining market, which is likely to cause a greater decline in the net asset value of the common shares than if the Trust were not leveraged, which may result in a greater decline in the market price of the common shares; • leverage may increase operating costs, which may reduce total return. Any decline in the net asset value of the Trust’s investments will be borne entirely by the holders of common shares. Therefore, if the market value of the Trust’s portfolio declines, leverage will result in a greater decrease in net asset value to the holders of common shares than if the Trust 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.
Reverse Repurchase Agreements Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Reverse Repurchase Agreements Risk (BDJ, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI):
Dollar Rolls Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Dollar Rolls Risk (BME, BMEZ, BIGZ, BST and BSTZ):
When Issued and Delayed Delivery Securities and Forward Commitments Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										When-Issued and Delayed Delivery Securities and Forward Commitments Risk (BDJ, BME, BMEZ, BCX and BSTZ):
Short Sales Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Short Sales Risk (BDJ, BGY, BME, BMEZ, BCX, BST, BSTZ and BUI):
Repurchase Agreements and Purchase and Sale Contracts Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Repurchase Agreements and Purchase and Sale Contracts Risk (BDJ, BME, BMEZ, BCX and BSTZ):
Risks Associated with Private Company Investments [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Risks Associated with Private Company Investments (BDJ, BMEZ, BIGZ, BST and BSTZ): These companies generally have less predictable operating results, may from time to time be parties to litigation, may be engaged in rapidly changing businesses with products subject to a substantial risk of obsolescence, and may require substantial additional capital to support their operations, finance expansion or maintain their competitive position. These companies may have difficulty accessing the capital markets to meet future capital needs, which may limit their ability to grow or to repay their outstanding indebtedness upon maturity. In addition, the Trust’s investment also may be structured as pay-in-kind securities with minimal or no cash interest or dividends until the company meets certain growth and liquidity objectives. Typically, investments in private companies are in restricted securities that are not traded in public markets and subject to substantial holding periods, so that the Trust may not be able to resell some of its holdings for extended periods, which may be several years. There can be no assurance that the Trust will be able to realize the value of private company investments in a timely manner. • Late-Stage Private Companies Risk (BMEZ and BIGZ) – Investments in late-stage private companies involve greater risks than investments in shares of companies that have traded publicly on an exchange for extended periods of time. These investments may present significant opportunities for capital appreciation but involve a high degree of risk that may result in significant decreases in the value of these investments. The Trust may not be able to sell such investments when the Manager deems it appropriate to do so because they are not publicly traded. As such, these investments are generally considered to be illiquid until a company’s public offering (which may never occur) and are often subject to additional contractual restrictions on resale following any public offering that may prevent the Trust from selling its shares of these companies for a period of time. See “Illiquid Investments Risk.” Market conditions, developments within a company, investor perception or regulatory decisions may adversely affect a late-stage private company and delay or prevent such a company from ultimately offering its securities to the public. If a company does issue shares in an IPO, IPOs are risky and volatile and may cause the value of the Trust’s investment to decrease significantly. • Pre-IPO Securities Risk (BSTZ) – Investments in pre-IPO securities involve greater risks than investments in shares of companies that have traded publicly on an exchange for extended periods of time. These investments may present significant opportunities for capital appreciation but involve a high degree of risk that may result in significant decreases in the value of these investments. Issuers of pre-IPO securities may not have established products, experienced management or earnings history. The Trust may not be able to sell such investments when the Manager deems it appropriate to do so because they are not publicly traded. As such, these investments are generally considered to be illiquid until a company’s public offering (which may never occur) and are often subject to additional contractual restrictions on resale following any public offering that may prevent the Trust from selling its shares of these companies for a period of time. See “Illiquid Investments Risk.” Market conditions, developments within a company, investor perception or regulatory decisions may adversely affect an issuer of pre-IPO securities and delay or prevent such an issuer from ultimately offering its securities to the public. If a company does issue shares in an IPO, IPOs are risky and volatile and may cause the value of the Trust’s investment to decrease significantly.
Illiquid Investments Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Illiquid Investments
Investment Companies and ETFs Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Investment Companies and ETFs Risk (BME BMEZ BIGZ BCX BST BSTZ and BUI): The securities of other investment companies and ETFs in which the Trust may invest may be leveraged. As a result, the Trust may be indirectly exposed to leverage through an investment in such securities. An investment in securities of other investment companies and ETFs that use leverage may expose the Trust to higher volatility in the market value of such securities and the possibility that the Trust’s long-term returns on such securities (and, indirectly, the long-term returns of shares of the Trust) will be diminished. As with other investments, investments in other investment companies, including ETFs, are subject to market and selection risk. To the extent the Trust is held by an affiliated fund, the ability of the Trust itself to hold other investment companies may be limited.
Subsidiary Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Subsidiary Risk (BCX):
Securities Lending Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Securities Lending Risk (BDJ, BGY, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI):
Risk of Investing in the United States [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Risk of Investing in the United States (BGR, CII, BDJ, BOE, BME, BMEZ, BIGZ, BCX, BST, BSTZ and BUI):
Market Risk and Selection Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Market Risk and Selection Risk: An outbreak of an infectious coronavirus (COVID-19) that was first detected in December 2019 developed into a global pandemic that has resulted in numerous disruptions in the market and has had significant economic impact leaving general concern and uncertainty. Although vaccines have been developed and approved for use by various governments, the duration of the pandemic and its effects cannot be predicted with certainty. The impact of this coronavirus, and other epidemics and pandemics that may arise in the future, could affect the economies of many nations, individual companies and the market in general ways that cannot necessarily be foreseen at the present time.
Shareholder Activism Risk [Member]
General Description of Registrant [Abstract]
Risk [Text Block]										Shareholder Activism Risk: activism
Common Shares [Member]
Other Annual Expenses [Abstract]
Basis of Transaction Fees, Note [Text Block]										as a percentage of net assets attributable to common shares
General Description of Registrant [Abstract]
Lowest Price or Bid		$ 6.92	$ 7.47	$ 8.03	$ 8.26	$ 8.14	$ 8.08	$ 8.29	$ 9.15
Highest Price or Bid		7.91	8.39	8.6	9.36	9.5	9.71	9.96	10.43
Lowest Price or Bid, NAV		8.17	8.38	8.56	8.23	8.58	8.47	9.26	9.73
Highest Price or Bid, NAV		$ 8.68	$ 8.96	$ 8.76	$ 9.15	$ 9.49	$ 9.42	$ 10.26	$ 10.55
Highest Price or Bid, Premium (Discount) to NAV [Percent]		(8.87%)	(6.36%)	(1.83%)	2.30%	0.11%	3.08%	(2.92%)	(1.14%)
Lowest Price or Bid, Premium (Discount) to NAV [Percent]		(15.30%)	(10.86%)	(6.19%)	0.36%	(5.13%)	(4.60%)	(10.48%)	(5.96%)
Share Price		$ 7.69								$ 7.69
NAV Per Share		$ 8.82								$ 8.82
Latest Premium (Discount) to NAV [Percent]										(12.81%)
Capital Stock, Long-Term Debt, and Other Securities [Abstract]
Outstanding Security, Authorized [Shares]										40,000,000
Outstanding Security, Held [Shares]										186,135,109
Investment Objectives [Member]
General Description of Registrant [Abstract]
Investment Objectives and Practices [Text Block]										Investment Objective BlackRock Enhanced Equity Dividend Trust’s (BDJ) (the “Trust”) No assurance can be given that the Trust’s investment objectives will be achieved.
Investment Objectives and Policies [Member]
General Description of Registrant [Abstract]
Investment Objectives and Practices [Text Block]										BlackRock Enhanced Equity Dividend Trust (BDJ) The Trust’s primary investment objective is to provide current income and current gains, with a secondary objective of long-term capital appreciation. The Trust’s investment objectives are not fundamental and may be changed by the Board of Trustees without shareholder approval. The Trust seeks to achieve its investment objectives by investing in common stocks that pay dividends and have the potential for capital appreciation and by utilizing an option writing strategy to enhance distributions to its shareholders. The Trust uses an option strategy that writes options on approximately 50-60% of its total assets. Under normal market conditions, the Trust invests at least 80% of its total assets in dividend-paying equities and may invest up to 20% of its total assets in equity securities of issuers that do not pay dividends. The Trust may invest directly in securities or synthetically through the use of derivatives. To the extent the Trust invests in dividend-paying common stocks, BlackRock Advisors, LLC (the “Manager”) may emphasize those securities that: (i) are eligible to pay “qualified dividend” income, and/or (ii) make payments that are eligible for the dividends received deduction allowed to corporate taxpayers pursuant to Section 243 of the Internal Revenue Code of 1986, as amended (the “Code”). Long-term capital gains and qualified dividend income are currently eligible for reduced U.S. federal income tax rates for individuals. Long-term capital gains and qualified dividend income properly reported as being included in distributions of a regulated investment company (a “RIC”) to its individual shareholders are generally passed through to such shareholders and taxed at such reduced rates. Pursuant to Section 243 of the Code, corporations generally may deduct a portion of the dividend income they receive from domestic corporations. Corporate shareholders of a RIC generally are permitted to claim a deduction with respect to that portion of their dividend distributions attributable to amounts that the RIC reports as qualifying for the dividends received deduction. Although the Trust has the ability to borrow money for investment purposes, it has no current intention to do so. If, however, the Trust did use leverage, the use of leverage through borrowings may reduce the amount of dividends it can designate as qualifying for the dividends received deduction which will, in turn, limit the tax benefit to a corporate shareholder of investing in the Trust. Corporate shareholders should consider whether an investment in the Trust is appropriate in light of the Trust’s ability to borrow. No assurance can be given as to what percentage of the dividends paid on the Trust’s common stock will be eligible for: (i) the reduced U.S. federal income tax rate for qualified dividend income and long-term capital gains for individuals, or (ii) the dividends received deduction for corporate shareholders of the Trust. The Trust may invest up to 20% of its total assets in preferred securities. The Trust may invest up to 10% of its total assets in privately placed or restricted securities (including in Rule 144A securities, which are privately placed securities purchased by qualified institutional buyers), illiquid securities and securities in which no secondary market is readily available, including those of private companies. The Trust may invest in shares of real estate investment trusts. The Trust may invest up to 20% of its total assets in non-U.S. securities, which may include securities denominated in U.S. dollars or in foreign currencies or multinational currency units. The Trust may invest in foreign securities of emerging market issuers, but investments in such securities will not comprise more than 10% of its total assets. The Trust will consider a company a U.S. company and not a foreign company if it meets one or more of the following tests: (i) such company was organized in the United States; (ii) such company’s primary business office is in the United States; (iii) the principal trading market for such company’s assets are located in the United States; (iv) 50% or more of such company’s assets are located in the United States; or (v) 50% or more of such issuer’s revenues are derived from the United States. The Trust may enter into forward currency contracts to purchase or sell foreign currencies for a fixed amount of U.S. dollars or another foreign currency. The Trust may enter into are interest rate swaps and the purchase or sale of interest rate caps and floors. The Trust expects to enter into these transactions primarily to preserve a return or spread on a particular investment or portion of its portfolio as a duration management technique or to protect against any increase in the price of securities the Trust anticipates purchasing at a later date. The Trust intends to use these transactions for hedging and risk management purposes and not as a speculative investment. The Trust will not sell interest rate caps or floors that it does not own. The Trust will only enter into interest rate swap, cap or floor transactions with counterparties the Investment Advisor believes to be creditworthy at the time they enter into such transactions. The Trust will not make a short sale if, after giving effect to such sale, the market value of all securities sold short exceeds 25% of the value of the Trust’s total assets or the Trust’s aggregate short sales of a particular class of securities exceeds 25% of the outstanding securities of that class. The Trust may also make short sales “against the box” without respect to such limitations. Leverage: The Trust currently does not intend to incur indebtedness or issue preferred shares for investment purposes, except in connection with derivative instruments such as exchange listed and over-the-counter put and call options on securities, financial futures, equity indices, and other financial instruments, purchase and sell futures contracts and options thereon, swaps, forward foreign currency contracts and various interest rate transactions, short sales, repurchase agreements, reverse repurchase agreements, when issued or forward commitment transactions and similar investment strategies. The Trust may enter into derivative transactions that have leverage embedded in them.
[1]If the common shares are sold to or through underwriters, the Prospectus Supplement will set forth any applicable sales load and the estimated offering expenses. Trust shareholders will pay all offering expenses involved with an offering.[2]Computershare Trust Company, N.A. (the “Reinvestment Plan Agent”) fees for the handling of the reinvestment of dividends will be paid by BDJ. However, shareholders will pay a $0.02 per share fee incurred in connection with open-market purchases, which will be deducted from the value of the dividend. Shareholders will also be charged a $0.02 per share fee if a shareholder directs the Reinvestment Plan Agent to sell the common shares held in a dividend reinvestment account. Per share fees include any applicable brokerage commissions the Reinvestment Plan Agent is required to pay.[3]BDJ and the Manager have entered into a fee waiver agreement (the “Fee Waiver Agreement”), pursuant to which the Manager has contractually agreed to waive the investment advisory fees with respect to any portion of BDJ’s assets attributable to investments in any equity and fixed-income mutual funds and exchange-traded funds (“ETFs”) managed by the Manager or its affiliates that have a contractual fee, through June 30, 2025. In addition, pursuant to the Fee Waiver Agreement, the Manager has contractually agreed to waive its investment advisory fees by the amount of investment advisory fees BDJ pays to the Manager indirectly through its investment in money market funds managed by the Manager or its affiliates, through June 30, 2025. The Fee Waiver Agreement may be terminated at any time, without the payment of any penalty, only by BDJ (upon the vote of a majority of the Trustees who are not “interested persons” (as defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”), of BDJ (the “Independent Trustees”)) or a majority of the outstanding voting securities of BDJ), upon 90 days’ written notice by BDJ to the Manager.[4]The total annual expenses do not correlate to the ratios to average net assets shown in BDJ’s Financial Highlights for the year ended December 31, 2023, which do not include acquired fund fees and expenses.