Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Dec. 31, 2011
Marvin & Palmer Large Cap Growth Fund (Prospectus Summary) | Marvin & Palmer Large Cap Growth Fund
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return, Heading	rr_RiskReturnHeading	SUMMARY SECTION
Investment Objective, Heading	rr_ObjectiveHeading	Investment Goal
investment Objective, Primary	rr_ObjectivePrimaryTextBlock	The Fund seeks long-term capital appreciation.
Expense, Heading	rr_ExpenseHeading	Expenses and Fees
Expense, Narrative	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund ("Shares").
Shareholder Fees, Caption	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses, Caption	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover, Heading	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover	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 rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Total 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 95.16% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	95.16%
Expense Example, Heading	rr_ExpenseExampleHeading	Example
Expense Example, Narrative	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 the period. The Example also assumes that your investment has a 5% return each year and that the operating expenses of the Fund remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Investment Strategy, Heading	rr_StrategyHeading	Principal Investment Strategies
Investment Strategy, Narrative	rr_StrategyNarrativeTextBlock	Investments: The Fund pursues its investment goal by investing under normal circumstances at least 80% of its net assets in large cap growth equity securities that the Adviser believes offer the prospect of long-term capital appreciation. Large cap equity securities generally refer to companies in the Russell 1000® Growth Index, although the Fund may invest in securities not included in the Index. As of November 30, 2011, the market capitalization range for companies in the Index was $107 million to $396.3 billion. The Adviser generally intends to purchase securities of issuers with a market capitalization of $5 billion or more at the time of investment. The Fund may invest in securities of foreign issuers that are traded or denominated in U.S. dollars through American Depositary Receipts listed on a national securities exchange or traded in the over-the-counter market. The Fund will notify shareholders in writing at least 60 days prior to any change of its policy to invest at least 80% of its net assets in large cap growth equity securities. The Fund may participate as a purchaser in initial public offerings of securities (an "IPO"). An IPO is a company's first offering of stock to the public. The Fund may also purchase securities of unseasoned issuers. The Fund reserves the right to hold up to 100% of its assets as a temporary defensive measure in cash and money market instruments. To the extent the Fund employs a temporary defensive measure, the Fund may not achieve its investment goal. Strategies: The Adviser uses a proprietary relative price strength model and focused fundamental research as part of a three step investment process to identify stocks that the Adviser believes have rising earnings expectations. First, the Adviser relies on a relative price strength model that is focused on long term trends to analyze sectors and individual stocks based on relative price movement. Companies that can be categorized as having positive price strength, i.e. leading the benchmark, become the focus of fundamental analysis by the portfolio managers. Second, the Adviser uses fundamental analysis to evaluate particular sectors and stocks identified as having positive price strength based on the results of the relative price strength model. The Adviser analyzes growth trends and competitive dynamics, including an analysis of the outlook for prices, costs, and volumes for the industry's key players. At the company level, the Adviser looks for superior, sustainable long-term growth. The Adviser evaluates three primary factors to predict the long-term growth rate for a stock: franchise quality (for example, top line growth rate for the industry and the company, the company's competitive advantage, and the company's key competitors), management quality and balance sheet quality (for example, sufficient internal capital generation to grow the company and risk of bankruptcy). Third, the Adviser applies the results of steps one and two to construct the Fund's portfolio by setting sector allocations and selecting stocks. No stock can be purchased unless it has passed the first two steps of the investment process. The Adviser uses a target range of stocks (35-55) and a minimum position size of 0.25% of the Fund's portfolio for each portfolio security purchased.
Risk, Heading	rr_RiskHeading	Principal Risks
Risk, Narrative	rr_RiskNarrativeTextBlock	Investing in any mutual fund involves risk, including the risk that you may receive little or no return on your investment, the risk that the Fund could underperform other possible investments, and the risk that you may lose part or all of the money you invest. Before you invest in the Fund, you should carefully evaluate the risks. You could lose money on your investment in the Fund if any of the following occurs: o The U.S. stock market goes down. o Growth stocks or stocks of large capitalization companies temporarily fall out of favor with investors or are more volatile than the rest of the U.S. market as a whole. o Companies in which the Fund invests suffer unexpected losses or lower than expected earnings or their securities become difficult or impossible to sell at the time and price the Adviser would like. o The Adviser's judgment about the attractiveness or potential appreciation of a particular security or sector proves to be wrong or the Fund misses out on an investment opportunity because the assets necessary to take advantage are tied up in less advantageous investments. o Political and economic events unique to a country or region in which the Fund invests negatively affect the value or liquidity of the Fund's holdings in that country or region. In addition, the Fund may invest in initial public offerings which entail special risks, including limited operating history of the issuing companies, unseasoned trading, and limited liquidity.
Risk, Lose Money	rr_RiskLoseMoney	Investing in any mutual fund involves risk, including the risk that you may receive little or no return on your investment, the risk that the Fund could underperform other possible investments, and the risk that you may lose part or all of the money you invest.
Bar Chart and Performance Table, Heading	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance, Narrative	rr_PerformanceNarrativeTextBlock	The chart below illustrates the long-term performance of the Fund. The information shows you how the Fund's performance has varied year by year since its inception and provides some indication of the risks of investing in the Fund. The chart assumes reinvestment of dividends and distributions. As with all such investments, past performance (before and after taxes) is not an indication of future results. Performance reflects fee waivers in effect. If fee waivers were not in place, the Fund's performance would be reduced. Updated performance information is available at 1-877-821-2117.
Performance, Information Illustrates Variability of Returns	rr_PerformanceInformationIllustratesVariabilityOfReturns	The chart below illustrates the long-term performance of the Fund.
Performance, Availability Phone Number	rr_PerformanceAvailabilityPhone	1-877-821-2117
Performance, Past Does Not Indicate Future	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	TOTAL RETURNS FOR THE CALENDAR YEAR ENDED DECEMBER 31
Bar Chart, Closing	rr_BarChartClosingTextBlock	Best and Worst Quarterly Performance (for the periods in the chart above): Best Quarter: 16.24% (Qtr. ended September 30, 2010) Worst Quarter (23.18)% (Qtr. ended December 31, 2008) Year-to-date total return for the nine months ended September 30, 2011: (12.84)%.
Performance Table, Heading	rr_PerformanceTableHeading	Average Annual Total Returns
Index No Deduction for Fees, Expenses, Taxes	rr_IndexNoDeductionForFeesExpensesTaxes	reflects no deduction for fees, expenses or taxes
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	After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table, One Class of after Tax Shown	rr_PerformanceTableOneClassOfAfterTaxShown	Actual after-tax returns depend on an investor's tax situation and may differ from those shown.
Performance Table, Narrative	rr_PerformanceTableNarrativeTextBlock	The table below compares the average annual total returns for the Fund both before and after taxes for the past calendar year and since inception to the average annual total returns of a broad-based securities market index for the same periods.
Average Annual Returns, Caption	rr_AverageAnnualReturnCaption	Average Annual Total Returns for the Periods Ended December 31, 2010
Marvin & Palmer Large Cap Growth Fund (Prospectus Summary) | Marvin & Palmer Large Cap Growth Fund | Russell 1000® Growth Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Russell 1000® Growth Index (reflects no deduction for fees, expenses or taxes)	[1]
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	16.71%
Average Annual Returns, 3 Years	ck0000831114_AverageAnnualReturnYear03	(0.47%)
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	(0.49%)	[2]
Marvin & Palmer Large Cap Growth Fund (Prospectus Summary) | Marvin & Palmer Large Cap Growth Fund | Marvin & Palmer Large Cap Growth Fund
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption Fee (as a percentage of amount redeemed, if applicable)	rr_RedemptionFeeOverRedemption	none
Exchange Fee	rr_ExchangeFee	none
Management fees	rr_ManagementFeesOverAssets	0.65%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	2.57%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	3.22%
Fee waivers and expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(2.42%)	[3]
Net expenses	rr_NetExpensesOverAssets	0.80%
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	2012-12-31
Expense Example, With Redemption, 1 Year	rr_ExpenseExampleYear01	82
Expense Example, With Redemption, 3 Years	rr_ExpenseExampleYear03	765
Expense Example, With Redemption, 5 Years	rr_ExpenseExampleYear05	1,472
Expense Example, With Redemption, 10 Years	rr_ExpenseExampleYear10	3,354
Annual Return 2008	rr_AnnualReturn2008	(46.15%)
Annual Return 2009	rr_AnnualReturn2009	17.16%
Annual Return 2010	rr_AnnualReturn2010	19.40%
Year to Date Return, Label	rr_YearToDateReturnLabel	Year-to-date total return
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2011
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	(12.84%)
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2010
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	16.24%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(23.18%)
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Returns Before Taxes
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	19.40%
Average Annual Returns, 3 Years	ck0000831114_AverageAnnualReturnYear03	(9.01%)
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	(3.44%)	[2]
Marvin & Palmer Large Cap Growth Fund (Prospectus Summary) | Marvin & Palmer Large Cap Growth Fund | Marvin & Palmer Large Cap Growth Fund | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Returns After Taxes on Distributions	[4]
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	19.40%
Average Annual Returns, 3 Years	ck0000831114_AverageAnnualReturnYear03	(9.06%)
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	(3.49%)	[2]
Marvin & Palmer Large Cap Growth Fund (Prospectus Summary) | Marvin & Palmer Large Cap Growth Fund | Marvin & Palmer Large Cap Growth Fund | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Average Annual Returns, Label	rr_AverageAnnualReturnLabel	Returns After Taxes on Distributions and Sale of Fund Shares
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	12.61%
Average Annual Returns, 3 Years	ck0000831114_AverageAnnualReturnYear03	(7.58%)
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	(2.93%)	[2]

[1] The Russell 1000® Growth Index is an unmanaged index composed of the securities in the Russell 1000® Index with higher price-to-book ratios and higher forecasted growth values. The Russell 1000® Index is comprised of the 1,000 largest U.S. companies based on total market capitalization.

[2] Commenced operations on June 29, 2007.

[3] Marvin & Palmer Associates, Inc. (the "Adviser") has contractually agreed to forgo its advisory fee and/or reimburse expenses in order to limit Total Annual Fund Operating Expenses (excluding certain items discussed below) to 0.80% of the Fund's average daily net assets. In determining the Adviser's obligation to waive advisory fees and/or reimburse expenses, the following expenses are not taken into account and could cause net Total Annual Fund Operating Expenses to exceed 0.80%: acquired fund fees and expenses, brokerage commissions, extraordinary items, interest or taxes. This contractual limitation is in effect until December 31, 2012 and may not be terminated without the approval of the Board of Directors of The RBB Fund, Inc. The Adviser may discontinue these arrangements at any time after December 31, 2012. If at any time during the three years ending March 4, 2015 the Advisory Agreement is in effect, the Fund's Total Annual Fund Operating Expenses for that year are less than 0.80%, the Adviser is entitled to reimbursement by the Fund of the advisory fees forgone and other payments remitted by the Adviser to the Fund during such three-year period.

[4] 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 an investor's tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. The table, like the bar chart, provides some indication of the risks of investing in the Fund by showing how the Fund's average annual total returns for the one year and since inception periods compare with those of a broad measure of market performance.