v3.25.4
Label Element Value
Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk/Return [Heading] oef_RiskReturnHeading Old Westbury All Cap Core Fund
Objective [Heading] oef_ObjectiveHeading Investment Goal
Objective, Primary [Text Block] oef_ObjectivePrimaryTextBlock

The Fund’s goal is to seek long-term capital appreciation.

Expense Heading [Optional Text] oef_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] oef_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table or example below.

Operating Expenses Caption [Optional Text] oef_OperatingExpensesCaption Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] oef_ExpenseExampleHeading Example
Expense Example Narrative [Text Block] oef_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 below and then redeem all of your shares at the end of these 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:

Portfolio Turnover [Heading] oef_PortfolioTurnoverHeading Portfolio Turnover
Portfolio Turnover [Text Block] oef_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 transactions costs and may result in higher taxes when Fund 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 fiscal year ended October 31, 2025, the Fund’s portfolio turnover rate was 38% of the average value of its portfolio.

Portfolio Turnover, Rate oef_PortfolioTurnoverRate 38.00%
Strategy [Heading] oef_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] oef_StrategyNarrativeTextBlock

The Fund pursues its investment goal by investing in a diversified portfolio of equity and equity-related securities of any market capitalization. The Fund has no restrictions as to the size of the companies in which it invests. The Fund may invest in what generally are considered small-cap stocks, mid-cap stocks and large-cap stocks. The Fund may focus its investments in one of those categories, two of them or all of them, and may change the allocation of its investments at any time.

 

The Fund invests in a portfolio of securities the Adviser believes has the potential for long-term capital appreciation. The Fund invests primarily in securities listed on securities exchanges or actively traded in over-the-counter markets. The securities may be listed or traded in the form of American Depositary Receipts (“ADRs”), Global Depositary Receipts (“GDRs”), or other types of depositary receipts (including non-voting depositary receipts) or dual listed securities. The foreign securities in which the Fund may invest may be issued by issuers located in emerging market or developing market countries. The Fund also may invest in exchange-traded funds (“ETFs”) and a variety of derivatives, including futures, options and other derivative instruments, to seek to increase or seek to hedge, or protect, its exposure to, for example, movements in the securities markets.

Bar Chart and Performance Table [Heading] oef_BarChartAndPerformanceTableHeading Performance Information
Performance Narrative [Text Block] oef_PerformanceNarrativeTextBlock

The bar chart and the performance table shown below provide some indication of the risks of investing in the Fund by showing changes in its performance from year to year and by comparing the Fund’s performance to a broad-based securities index, the MSCI ACWI Investable Market Index (Net). In addition, the Fund compares its performance to a blended benchmark, as an additional benchmark, consisting of a 90% weighting in the MSCI USA Index (Gross) and a 10% weighting in the MSCI ACWI ex USA Index (Net). The Net performance figures of each index reflect no deductions for fees, expenses or income taxes, except foreign withholding taxes. For additional information about the indexes, please see the section entitled “Index Descriptions.”

 

Past performance (before and after taxes) does not necessarily predict future performance. Fund performance shown below reflects fees, waivers and/or expense reimbursements during such period and reinvestment of distributions, if any. Without waivers/reimbursements, performance would have been lower.

Prior to December 30, 2016, the Fund was named the Old Westbury Large Cap Core Fund and operated under a different investment strategy. The performance information shown below before such date represents the Fund’s prior investment strategies.

Performance Information Illustrates Variability of Returns [Text] oef_PerformanceInformationIllustratesVariabilityOfReturns The bar chart and the performance table shown below provide some indication of the risks of investing in the Fund by showing changes in its performance from year to year and by comparing the Fund’s performance to a broad-based securities index, the MSCI ACWI Investable Market Index (Net).
Performance Additional Market Index [Text] oef_PerformanceAdditionalMarketIndex In addition, the Fund compares its performance to a blended benchmark, as an additional benchmark, consisting of a 90% weighting in the MSCI USA Index (Gross) and a 10% weighting in the MSCI ACWI ex USA Index (Net).
Performance Past Does Not Indicate Future [Text] oef_PerformancePastDoesNotIndicateFuture Past performance (before and after taxes) does not necessarily predict future performance.
Bar Chart [Heading] oef_BarChartHeading Annual Total Returns (for calendar years ended December 31st)
Bar Chart Closing [Text Block] oef_BarChartClosingTextBlock

During the periods shown in the bar chart, the highest return for a quarter was 23.76% (quarter ended 6/30/2020) and the lowest return for a quarter was (17.97)% (quarter ended 3/31/2020).

Highest Quarterly Return, Label [Optional Text] oef_HighestQuarterlyReturnLabel highest return for a quarter
Highest Quarterly Return, Date oef_BarChartHighestQuarterlyReturnDate Jun. 30, 2020
Highest Quarterly Return oef_BarChartHighestQuarterlyReturn 23.76%
Lowest Quarterly Return, Label [Optional Text] oef_LowestQuarterlyReturnLabel lowest return for a quarter
Lowest Quarterly Return, Date oef_BarChartLowestQuarterlyReturnDate Mar. 31, 2020
Lowest Quarterly Return oef_BarChartLowestQuarterlyReturn (17.97%)
Index No Deduction for Fees, Expenses, or Taxes [Text] oef_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or income taxes, except foreign withholding taxes)
Performance Table Uses Highest Federal Rate oef_PerformanceTableUsesHighestFederalRate After-tax returns are calculated using the historical highest individual federal marginal income tax rate, and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred oef_PerformanceTableNotRelevantToTaxDeferred Actual after-tax returns depend on the investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to shareholders who hold Fund shares through tax-deferred arrangements such as 401(k) plans or Individual Retirement Accounts.
Performance Table Explanation after Tax Higher oef_PerformanceTableExplanationAfterTaxHigher The Fund Return After Taxes on Distributions and Sale of Shares may be higher than other return figures when a capital loss occurs upon the redemption of Fund shares.
Performance Table Closing [Text Block] oef_PerformanceTableClosingTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rate, 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. After-tax returns shown are not relevant to shareholders who hold Fund shares through tax-deferred arrangements such as 401(k) plans or Individual Retirement Accounts. The Fund Return After Taxes on Distributions and Sale of Shares may be higher than other return figures when a capital loss occurs upon the redemption of Fund shares.

Average Annual Return, Caption [Optional Text] oef_AverageAnnualReturnCaption Average Annual Total Returns (for the periods ended 12/31/2025)
Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Risk Not Insured [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock The shares offered by this Prospectus are not deposits or obligations of any bank, are not endorsed or guaranteed by any bank and are not insured or

guaranteed by the U.S. Government, the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency. You could lose all or a part of your investment in the Fund.

Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Risk Lose Money [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock You could lose all or a part of your investment in the Fund.
Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Stock Market/Company Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

Stock Market/Company Risk—Stock markets are volatile and can decline significantly in response to real or perceived changes to the issuer, industry, market, economic, political, regulatory, geopolitical, pandemics and epidemics and other conditions. The value of an equity security can decline significantly in response to these conditions. After other claims are satisfied, common stockholders participate in company profits on a pro-rata basis and profits may be paid out in dividends or reinvested in the company to help it grow.

Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Market Capitalization Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

Market Capitalization Risk—To the extent the Fund invests in securities of small-, mid-, or large-cap companies, it takes on the associated risks. At times, any one of these market capitalizations may be out of favor with investors. Compared to small- and mid-cap companies, large-cap companies may be less responsive to changes and opportunities. Compared to large-cap companies, small- and mid-cap companies may depend on a more limited management group, may have a shorter history of operations, and may have limited product lines, markets or financial resources. The securities of small-and mid-cap companies are often more volatile and relatively less liquid than the securities of larger companies and may be more affected than other types of securities by the underperformance of a sector or during market downturns.

Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Foreign Market Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

Foreign Market Risk—Exposure to foreign markets through issuers or currencies can involve heightened risks relating to market, economic, political, regulatory, geopolitical, social, pandemics and epidemics or other conditions and additional risks. International trade tensions involving certain countries and their trading counterparties may arise from time to time which can result in trade tariffs (including those imposed by the U.S. or foreign governments), embargoes, trade limitations, trade wars and other negative consequences. Such actions and consequences may ultimately result in a significant reduction in international trade, an oversupply of certain manufactured goods, devaluations of existing inventories and potentially the failure of individual companies and/or large segments of certain country’s export industry with a potentially severe negative impact to the Fund. In addition, the securities of foreign companies also may be subject to the imposition of economic sanctions; more or less foreign government regulation; less public information; less stringent investor protections; and less stringent accounting, corporate governance, financial reporting and disclosure standards than domestic companies. The risks of foreign investments are increased in emerging markets which may, among other adverse developments or conditions, experience hyperinflation and have far lower trading volumes and less liquidity than developed markets. Currency exchange rates may fluctuate significantly over short periods of time. Such fluctuations in foreign currency exchange rates can affect the value of the Fund’s portfolio. Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted.

Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Developing Market Countries Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

Developing Market Countries Risk—The Fund’s investments in developing market countries are subject to all of the risks of foreign investing generally, and have heightened and additional risks due to a lack of established legal, political, business and social frameworks to support securities markets.

Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Exchange-Traded Funds Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

Exchange-Traded Funds Risk—Exchange-traded funds or ETFs are subject to many of the same risks associated with individual stocks and other investments, including market risk where the market as a whole, or the specific sector in which an ETF invests, may decline. ETFs may trade at a premium or discount to the aggregate value of the underlying securities. A shareholder will be charged fees and expenses not only on Fund shares held directly but also indirectly on the ETF shares that a Fund purchases and the Fund’s investment in an ETF will subject the Fund to the risks of the ETF.

Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Derivatives Risk [Member]  
Prospectus [Line Items] oef_ProspectusLineItems  
Risk [Text Block] oef_RiskTextBlock

Derivatives Risk—Derivatives are subject to a number of risks, including changes in the market price of the underlying securities, credit risk with respect to the counterparty to the derivative instruments and the risk of loss due to changes in interest rates. The use of certain derivatives may also have a leveraging effect, which may increase the Fund’s sensitivity to adverse market movements and may exaggerate a loss. Losses may arise as the value of the contract decreases due to, among other potentially adverse events, an unfavorable change in the price of the underlying security or commodity or if the counterparty does not perform under the contract. The use of derivatives can lead to losses because of relatively small adverse movements in the price or value of the underlying security, asset, index or reference rate, which may be magnified by or potentially unlimited as a result of certain features of the derivatives.

Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund  
Prospectus [Line Items] oef_ProspectusLineItems  
Management Fees (as a percentage of Assets) oef_ManagementFeesOverAssets 0.67%
Other Expenses (as a percentage of Assets): oef_OtherExpensesOverAssets 0.28%
Expenses (as a percentage of Assets) oef_ExpensesOverAssets 0.95%
Expense Example, with Redemption, 1 Year oef_ExpenseExampleYear01 $ 97
Expense Example, with Redemption, 3 Years oef_ExpenseExampleYear03 303
Expense Example, with Redemption, 5 Years oef_ExpenseExampleYear05 525
Expense Example, with Redemption, 10 Years oef_ExpenseExampleYear10 $ 1,166
Old Westbury All Cap Core Fund | 90% MSCI USA Index (Gross) & 10% MSCI ACWI ex USA Index (Net) (reflects no deduction for fees, expenses or income taxes, except foreign withholding taxes for the (Net) index component)  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 19.18%
Average Annual Return, Percent oef_AvgAnnlRtrPct 13.30%
Average Annual Return, Percent oef_AvgAnnlRtrPct 14.18%
Old Westbury All Cap Core Fund | MSCI ACWI Investable Market Index (Net) (reflects no deduction for fees, expenses or income taxes, except foreign withholding taxes)  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 22.06%
Average Annual Return, Percent oef_AvgAnnlRtrPct 10.75%
Average Annual Return, Percent oef_AvgAnnlRtrPct 11.45%
Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund  
Prospectus [Line Items] oef_ProspectusLineItems  
Annual Return [Percent] oef_AnnlRtrPct 7.32%
Annual Return [Percent] oef_AnnlRtrPct 20.93%
Annual Return [Percent] oef_AnnlRtrPct (4.02%)
Annual Return [Percent] oef_AnnlRtrPct 32.12%
Annual Return [Percent] oef_AnnlRtrPct 23.63%
Annual Return [Percent] oef_AnnlRtrPct 25.85%
Annual Return [Percent] oef_AnnlRtrPct (22.13%)
Annual Return [Percent] oef_AnnlRtrPct 25.92%
Annual Return [Percent] oef_AnnlRtrPct 21.31%
Annual Return [Percent] oef_AnnlRtrPct 10.38%
Average Annual Return, Percent oef_AvgAnnlRtrPct 10.38%
Average Annual Return, Percent oef_AvgAnnlRtrPct 10.57%
Average Annual Return, Percent oef_AvgAnnlRtrPct 12.89%
Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | After Taxes on Distributions  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 8.37%
Average Annual Return, Percent oef_AvgAnnlRtrPct 8.81%
Average Annual Return, Percent oef_AvgAnnlRtrPct 11.47%
Old Westbury All Cap Core Fund | Old Westbury All Cap Core Fund | After Taxes on Distributions and Sales  
Prospectus [Line Items] oef_ProspectusLineItems  
Average Annual Return, Percent oef_AvgAnnlRtrPct 7.55%
Average Annual Return, Percent oef_AvgAnnlRtrPct 8.16%
Average Annual Return, Percent oef_AvgAnnlRtrPct 10.46%