Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	BLACKROCK FUNDS
Prospectus Date	rr_ProspectusDate	Jan. 28, 2013
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Overview Key Facts About BlackRock Global Opportunities Portfolio
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The investment objective of BlackRock Global Opportunities Portfolio (“Global Opportunities” or the “Fund”), a series of BlackRock FundsSM (the “Trust”), is to provide long-term capital appreciation.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of Global Opportunities. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”). More information about these and other discounts is available from your financial professional and in the “Details About the Share Classes” section on page 47 of the Fund’s prospectus and in the “Purchase of Shares” section on page II-58 of the Fund’s statement of additional information.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	February 1, 2015
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover:
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 122% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	122.00%
Expenses Deferred Charges [Text Block]	rr_ExpensesDeferredChargesTextBlock	A contingent deferred sales charge ("CDSC") of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at time of purchase as part of an investment of $1,000,000 or more.
Expense Breakpoint Discounts [Text]	rr_ExpenseBreakpointDiscounts	You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the fund complex advised by BlackRock Advisors, LLC (“BlackRock”).
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	25,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example:
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example, No Redemption, By Year, Caption [Text]	rr_ExpenseExampleNoRedemptionByYearCaption	You would pay the following expenses if you did not redeem your shares:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies of the Fund
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal conditions, Global Opportunities will invest at least 75% of its total assets in global equity securities of any market capitalization, selected for their above-average return potential. The Fund seeks to buy primarily common stock but may also invest in preferred stock and convertible securities. The Fund may invest up to 25% of its total assets in stocks of issuers in emerging market countries. The Fund may invest up to 25% of its total assets in global fixed income securities, including corporate bonds, U.S. government debt securities, non-U.S. government and supranational debt securities, asset-backed securities, mortgage-backed securities, emerging market debt securities and non-investment grade debt securities (high yield or junk bonds). Investment in fixed income securities will be made on an opportunistic basis. Securities will be identified based on factors such as relative value and earnings estimate revisions. From time to time, the Fund may invest in shares of companies through initial public offerings (“IPOs”). The Fund will invest in securities of non-U.S. issuers that can be U.S. dollar based or non-U.S. dollar based on a hedged or unhedged basis. The Fund may enter into currency transactions on a hedged or unhedged basis in order to seek total return. The Fund may, when consistent with the Fund’s investment objective, buy or sell options or futures on a security or an index of securities and may buy options on a currency or a basket of currencies, or enter into foreign currency transactions, including swaps (collectively, commonly known as derivatives). The Fund typically uses derivatives as a substitute for taking a position in the underlying asset and/or as part of a strategy designed to reduce exposure to other risks, such as currency risk. The Fund may also use derivatives to enhance returns, in which case their use would involve leveraging risk. The Fund may seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as reverse repurchase agreements or dollar rolls). The Fund may also use forward foreign currency exchange contracts (obligations to buy or sell a currency at a set rate in the future).
Risk [Heading]	rr_RiskHeading	Principal Risks of Investing in the Fund
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Risk is inherent in all investing. The value of your investment in Global Opportunities, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks of investing in the Fund. Convertible Securities Risk — The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest or dividends when due, and their market value may change based on changes in the issuer’s credit rating or the market’s perception of the issuer’s creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock. Debt Securities Risk — Debt securities, such as bonds, involve credit risk. Credit risk is the risk that the borrower will not make timely payments of principal and interest. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also affect the value of the Fund’s investment in that issuer. The degree of credit risk depends on the issuer’s financial condition and on the terms of the securities. Debt securities are also subject to interest rate risk. Interest rate risk is the risk that the value of a debt security may fall when interest rates rise. In general, the market price of debt securities with longer maturities will go up or down more in response to changes in interest rates than the market price of shorter term securities. Derivatives Risk — The Fund’s use of derivatives may reduce the Fund’s returns and/or increase volatility. Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation. A risk of the Fund’s use of derivatives is that the fluctuations in their values may not correlate perfectly with the overall securities markets. The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately. Derivatives may give rise to a form of leverage and may expose the Fund to greater risk and increase its costs. Recent legislation calls for new regulation of the derivatives markets. The extent and impact of the regulation is not yet known and may not be known for some time. New regulation may make derivatives more costly, may limit the availability of derivatives, or may otherwise adversely affect the value or performance of derivatives. Emerging Markets Risk — Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets may be considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging securities markets have far lower trading volumes and less liquidity than developed markets. Equity Securities Risk — Stock markets are volatile. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions. Foreign Securities Risk — Foreign investments often involve special risks not present in U.S. investments that can increase the chances that the Fund will lose money. These risks include: — The Fund 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 Fund’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 may prohibit or impose substantial restrictions on foreign investments in their capital markets or in certain industries. — 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 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. These events may spread to other countries in Europe, including countries that do not use the Euro. These events may affect the value and liquidity of certain of the Fund’s investments. Investment Style Risk — Under certain market conditions, growth investments have performed better during the later stages of economic expansion. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles. Leverage Risk — Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Fund to greater risk and increase its costs. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations or to meet any required asset segregation requirements. Increases and decreases in the value of the Fund’s portfolio will be magnified when the Fund uses leverage. Market Risk and Selection Risk — Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money. Mid-Cap Securities Risk — The securities of mid-cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies. “New Issues” Risk — “New Issues” are initial public offerings of equity securities of U.S. and non-U.S. issuers. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the initial public offering. Small Cap Securities Risk — Small cap companies may have limited product lines or markets. They may be less financially secure than larger, more established companies. They may depend on a more limited management group than larger capitalized companies.
Risk Lose Money [Text]	rr_RiskLoseMoney	You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The information shows you how Global Opportunities’ performance has varied year by year and provides some indication of the risks of investing in the Fund. The table compares the average annual total returns of each class of the Fund’s shares with that of the MSCI All Country World Index. Class R Shares commenced operations on September 12, 2011, therefore the returns in the table for Class R Shares prior to commencement date are based on the Fund’s Institutional Shares, adjusted to reflect the fees and expenses applicable to Class R Shares. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If BlackRock and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s results can be obtained by visiting http://www.blackrock.com/funds or can be obtained by phone at (800) 882-0052.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The information shows you how Global Opportunities’ performance has varied year by year and provides some indication of the risks of investing in the Fund.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	(800) 882-0052
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	http://www.blackrock.com/funds
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	As with all such investments, past performance (before and after taxes) is not an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	Investor A Shares ANNUAL TOTAL RETURNS BlackRock Global Opportunities Portfolio As of 12/31
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	During the periods shown in the bar chart, the highest return for a quarter was 24.03% (quarter ended June 30, 2009) and the lowest return for a quarter was –21.57% (quarter ended December 31, 2008).
Performance Table Heading	rr_PerformanceTableHeading	As of 12/31/12 Average Annual Total Returns
Performance Table Does Reflect Sales Loads	rr_PerformanceTableDoesReflectSalesLoads	However, the table includes all applicable fees and sales charges.
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for Investor A Shares only, and the after-tax returns for Investor B, Investor C, Institutional and Class R Shares will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Investor A Shares only, and the after-tax returns for Investor B, Investor C, Institutional and Class R Shares will vary.
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | Investor A Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	5.25%
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none	[1]
Management Fees	rr_ManagementFeesOverAssets	0.90%
Distribution (12b-1) and/or Service Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.37%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.52%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.19%)	[2]
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	1.33%	[2]
1 Year	rr_ExpenseExampleYear01	653
3 Years	rr_ExpenseExampleYear03	944
5 Years	rr_ExpenseExampleYear05	1,275
10 Years	rr_ExpenseExampleYear10	2,211
2007	rr_AnnualReturn2007	21.09%
2008	rr_AnnualReturn2008	(38.79%)
2009	rr_AnnualReturn2009	34.50%
2010	rr_AnnualReturn2010	10.60%
2011	rr_AnnualReturn2011	(12.43%)
2012	rr_AnnualReturn2012	14.53%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	highest return
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	24.03%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	lowest return
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(21.57%)
1 Year	rr_AverageAnnualReturnYear01	8.54%
5 Years	rr_AverageAnnualReturnYear05	(2.85%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.22%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 31, 2006
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | Investor B Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	4.50%	[3]
Management Fees	rr_ManagementFeesOverAssets	0.90%
Distribution (12b-1) and/or Service Fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other Expenses	rr_OtherExpensesOverAssets	0.31%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	2.21%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.03%)	[2]
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	2.18%	[2]
1 Year	rr_ExpenseExampleYear01	671
3 Years	rr_ExpenseExampleYear03	1,035
5 Years	rr_ExpenseExampleYear05	1,379
10 Years	rr_ExpenseExampleYear10	2,365
1 Year	rr_ExpenseExampleNoRedemptionYear01	221
3 Years	rr_ExpenseExampleNoRedemptionYear03	685
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,179
10 Years	rr_ExpenseExampleNoRedemptionYear10	2,365
1 Year	rr_AverageAnnualReturnYear01	9.11%
5 Years	rr_AverageAnnualReturnYear05	(2.93%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.25%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 31, 2006
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | Investor C Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%	[4]
Management Fees	rr_ManagementFeesOverAssets	0.90%
Distribution (12b-1) and/or Service Fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other Expenses	rr_OtherExpensesOverAssets	0.42%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	2.32%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.18%)	[2]
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	2.14%	[2]
1 Year	rr_ExpenseExampleYear01	317
3 Years	rr_ExpenseExampleYear03	689
5 Years	rr_ExpenseExampleYear05	1,207
10 Years	rr_ExpenseExampleYear10	2,627
1 Year	rr_ExpenseExampleNoRedemptionYear01	217
3 Years	rr_ExpenseExampleNoRedemptionYear03	689
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,207
10 Years	rr_ExpenseExampleNoRedemptionYear10	2,627
1 Year	rr_AverageAnnualReturnYear01	12.68%
5 Years	rr_AverageAnnualReturnYear05	(2.57%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.24%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 31, 2006
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | Institutional Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Management Fees	rr_ManagementFeesOverAssets	0.90%
Distribution (12b-1) and/or Service Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.35%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.25%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.19%)	[2]
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	1.06%	[2]
1 Year	rr_ExpenseExampleYear01	108
3 Years	rr_ExpenseExampleYear03	358
5 Years	rr_ExpenseExampleYear05	649
10 Years	rr_ExpenseExampleYear10	1,477
1 Year	rr_AverageAnnualReturnYear01	14.87%
5 Years	rr_AverageAnnualReturnYear05	(1.50%)
Since Inception	rr_AverageAnnualReturnSinceInception	3.31%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 31, 2006
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | Class R Shares
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as percentage of offering price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Management Fees	rr_ManagementFeesOverAssets	0.90%
Distribution (12b-1) and/or Service Fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other Expenses	rr_OtherExpensesOverAssets	0.40%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.80%
Fee Waivers and/or Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.08%)	[2]
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	rr_NetExpensesOverAssets	1.72%	[2]
1 Year	rr_ExpenseExampleYear01	175
3 Years	rr_ExpenseExampleYear03	550
5 Years	rr_ExpenseExampleYear05	960
10 Years	rr_ExpenseExampleYear10	2,102
1 Year	rr_AverageAnnualReturnYear01	14.06%
5 Years	rr_AverageAnnualReturnYear05	(2.15%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.63%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 31, 2006
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | Return After Taxes on Distributions | Investor A Shares
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	8.38%
5 Years	rr_AverageAnnualReturnYear05	(2.91%)
Since Inception	rr_AverageAnnualReturnSinceInception	1.95%
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | Return After Taxes on Distributions and Sale of Shares | Investor A Shares
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	5.77%
5 Years	rr_AverageAnnualReturnYear05	(2.39%)
Since Inception	rr_AverageAnnualReturnSinceInception	1.82%
Investor, Institutional and R Shares | BLACKROCK GLOBAL OPPORTUNITIES PORTFOLIO | MSCI All Country World Index (Reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	16.13%
5 Years	rr_AverageAnnualReturnYear05	(1.16%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.85%

[1] A contingent deferred sales charge ("CDSC") of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at time of purchase as part of an investment of $1,000,000 or more.

[2] As described in the "Management of the Funds" section of the Fund's prospectus on pages 62-70, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) as a percentage of average daily net assets to 1.33% (for Investor A Shares), 2.18% (for Investor B Shares), 2.14% (for Investor C Shares), 1.06% (for Institutional Shares) and 1.72% (for Class R Shares) until February 1, 2015. The Fund may have to repay some of these waivers and/or reimbursements to BlackRock in the following two years. The agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.

[3] The CDSC is 4.50% if shares are redeemed in less than one year. The CDSC for Investor B Shares decreases for redemptions made in subsequent years. After six years there is no CDSC on Investor B Shares. (See the section "Details About the Share Classes - Investor B Shares" in the Fund's prospectus for the complete schedule of CDSCs.)

[4] There is no CDSC on Investor C Shares after one year.