Prospectus: Risk/Return: Document Type Document Period End Date Registrant Name Central Index Key Amendment Flag Amendment Description Trading Symbol Document Creation Date Document Effective Date Prospectus Date Document [Axis] Prospectus Performance Measure [Axis] Before Taxes After Taxes on Distributions and Sale of Shares After Taxes on Distributions and Sales After Taxes on Distributions After Taxes on Distributions Series [Axis] Series BULL PROFUND BULL PROFUND Member S000003059 [Member] Share Class [Axis] Share Classes C000012241 [Member] BULL PROFUND CLASS A,BULL PROFUND Member BULL PROFUND CLASS A,BULL PROFUND Member Investor Class Investor Class Shares C000008334 [Member] BULL PROFUND INVESTOR CLASS,BULL PROFUND Member Service Class C000008335 [Member] Service Class Shares BULL PROFUND SERVICE CLASS,BULL PROFUND Member Risk/Return [Heading] Objective [Heading] Objective, Primary [Text Block] Objective, Secondary [Text Block] Expense [Heading] Expense Narrative [Text Block] Shareholder Fees Caption [Text] Shareholder Fees [Table] Operating Expenses Caption [Text] Annual Fund Operating Expenses [Table] Expense Footnotes [Text Block] Expenses Deferred Charges [Text Block] Expenses Range of Exchange Fees [Text Block] Expense Example [Heading] Expense Example by Year [Heading] Expense Example Narrative [Text Block] Expense Example by, Year, Caption [Text] Expense Example, With Redemption [Table] Expense Example, No Redemption Narrative [Text Block] Expense Example, No Redemption, By Year, Caption [Text] Expense Example, No Redemption [Table] Expense Example Footnotes [Text Block] Expense Example Closing [Text Block] Portfolio Turnover [Heading] Portfolio Turnover [Text Block] Strategy [Heading] Strategy Narrative [Text Block] Risk [Heading] Risk Narrative [Text Block] Risk Footnotes [Text Block] Risk Closing [Text Block] Bar Chart and Performance Table [Heading] Performance Narrative [Text Block] Bar Chart Narrative [Text Block] Bar Chart [Heading] Bar Chart [Table] Bar Chart Footnotes [Text Block] Bar Chart Closing [Text Block] Performance Table Heading Performance [Table] Performance Table Narrative Market Index Performance [Table] Performance Table Footnotes Performance Table Closing [Text Block] Shareholder Fees: Wire Fee Shareholder Fee, Other Shareholder Fees Column [Text] Maximum Cumulative Sales Charge (as a percentage of Offering Price) Maximum Cumulative Sales Charge (as a percentage) Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) Maximum Deferred Sales Charge (as a percentage of Offering Price) Maximum Deferred Sales Charge (as a percentage) Maximum Sales Charge on Reinvested Dividends and Distributions (as a percentage) Redemption Fee (as a percentage of Amount Redeemed) Redemption Fee (as a percentage of Amount Redeemed) Redemption Fee Redemption Fee Exchange Fee (as a percentage of Amount Redeemed) Exchange Fee Maximum Account Fee (as a percentage of Assets) Maximum Account Fee Operating Expenses: Investment Advisory Fees Management Fees (as a percentage of Assets) Distribution and Service (12b-1) Fees Distribution and Service (12b-1) Fees Other Expenses Other Expenses (as a percentage of Assets): Other Expenses Total Annual Fund Operating Expenses Before Fee Waivers and Expense Reimbursements Expenses (as a percentage of Assets) Total Annual Fund Operating Expenses Before Fee Waivers and Expense Reimbursements Operating Expenses Column [Text] Distribution or Similar (Non 12b-1) Fees Recoupment Component1 Other Expenses Component2 Other Expenses Other Operating Expenses Component3 Other Expenses Acquired Fund Fees and Expenses Acquired Fund Fees and Expenses Fee Waiver/Reimbursement Fee Waiver or Reimbursement Fee Waiver or Reimbursement Fee Waivers/Reimbursements Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements Net Expenses (as a percentage of Assets) Total Annual Fund Operating Expenses After Fee Waivers and Expense Reimbursements Expense Example: 1 Year Expense Example, with Redemption, 1 Year 3 Years Expense Example, with Redemption, 3 Years 5 Years Expense Example, with Redemption, 5 Years 10 Years Expense Example, with Redemption, 10 Years Expense Example, By Year, Column [Text] Column Expense Example, No Redemption: Column Expense Example, No Redemption, By Year, Column [Text] 1 Year Expense Example, No Redemption, 1 Year Expense Example, No Redemption, 3 Years 3 Years Expense Example, No Redemption, 5 Years 5 Years Expense Example, No Redemption, 10 Years 10 Years Bar Chart Table: Caption Annual Return Caption [Text] Annual Return, Column [Text] Column Annual Return, Inception Date Inception Date Annual Return 1990 Annual Return 1991 Annual Return 1992 Annual Return 1993 Annual Return 1994 Annual Return 1995 Annual Return 1996 Annual Return 1997 Annual Return 1998 Annual Return 1999 Annual Return 2000 Annual Return 2001 2002 Annual Return 2002 Annual Return 2003 2003 Annual Return 2004 2004 2005 Annual Return 2005 2006 Annual Return 2006 Annual Return 2007 2007 Annual Return 2008 2008 Annual Return 2009 2009 Annual Return 2010 2010 Annual Return 2011 2011 Annual Return 2012 Annual Return 2013 Annual Return 2014 Annual Return 2015 Annual Return 2016 Annual Return 2017 Annual Return 2018 Annual Return 2019 Annual Return 2020 S And P Five Hundred. S And P Five Hundred [Member] S&P 500 Average Annual Return: One Year 1 Year Five Years 5 Years Ten Years 10 Years Since Inception Since Inception Inception Date Inception Date Label Risk/Return Detail [Table] Fee Waiver or Reimbursement over Assets, Date of Termination Portfolio Turnover, Rate Expense Breakpoint Discounts [Text] Expense Breakpoint, Minimum Investment Required [Amount] Expense Exchange Traded Fund Commissions [Text] Expenses Represent Both Master and Feeder [Text] Expenses Explanation of Nonrecurring Account Fee [Text] Other Expenses, New Fund, Based on Estimates [Text] Acquired Fund Fees and Expenses, Based on Estimates [Text] Expenses Other Expenses Had Extraordinary Expenses Been Included [Text] Expenses Restated to Reflect Current [Text] Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] Strategy Portfolio Concentration [Text] Risk Lose Money [Text] Risk Nondiversified Status [Text]