| Label | Element | Value | ||||||
|---|---|---|---|---|---|---|---|---|
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk/Return [Heading] | oef_RiskReturnHeading | GMO U.S. EQUITY FUND | ||||||
| Objective [Heading] | oef_ObjectiveHeading | Investment objective | ||||||
| Objective, Primary [Text Block] | oef_ObjectivePrimaryTextBlock |
High
total return.
|
||||||
| Expense Heading [Optional Text] | oef_ExpenseHeading | Fees and expenses | ||||||
| Expense Narrative [Text Block] | oef_ExpenseNarrativeTextBlock |
The
table below describes the fees and expenses that you may bear for each class of shares 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 and example below.
|
||||||
| Operating Expenses Caption [Optional Text] | oef_OperatingExpensesCaption | Annual Fund operating expenses (expenses that you bear each year as a percentage of the value of your investment) | ||||||
| Fee Waiver or Reimbursement over Assets, Date of Termination | oef_FeeWaiverOrReimbursementOverAssetsDateOfTermination | Sep. 30, 2027 | ||||||
| Other Expenses, New Fund, Based on Estimates [Text] | oef_OtherExpensesNewFundBasedOnEstimates | Because ETF Class shares of the Fund are new, “Other expenses” are estimated amounts for the current fiscal year based on the expenses of Class R6 shares of the Fund. | ||||||
| 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 funds. The example assumes
that you invest $10,000 in the Fund for the time periods indicated, regardless of whether or not you sell your shares at the end of such
periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses with respect
to ETF Class shares remain the same as those shown in the table. The one year amounts shown reflect the expense reimbursement and waiver
noted in the expense table. 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. A higher portfolio turnover rate may result in higher
transaction costs and, for holders of Fund shares subject to U.S. taxes, higher income taxes. These transaction costs, which are not reflected
in Annual Fund operating expenses or in the Example, affect the Fund’s performance. During its fiscal year ended February 28,
2026, the Fund’s portfolio turnover rate (excluding short-term investments) was 101%
of the average value of its portfolio securities. That portfolio turnover rate includes investments in U.S. Treasury Fund, which the Fund
uses as a short-term investment vehicle for cash management. The Fund’s portfolio turnover rate during its fiscal year ended February 28,
2026, excluding transactions in U.S. Treasury Fund and other short-term investments, was 95% of the average value of its portfolio securities.
|
||||||
| Portfolio Turnover, Rate | oef_PortfolioTurnoverRate | 101.00% | ||||||
| Strategy [Heading] | oef_StrategyHeading | Principal investment strategies | ||||||
| Strategy Narrative [Text Block] | oef_StrategyNarrativeTextBlock |
GMO
seeks to achieve the Fund’s investment objective by investing the Fund’s assets primarily in securities traded in U.S. equity
markets. GMO selects the securities the Fund buys and sells based on its evaluation of companies’ published financial information,
securities’ prices, equity and other markets, the overall global economy, and governmental policies.
In
selecting securities for the Fund, GMO uses a combination of proprietary quantitative investment methods to identify U.S. equities GMO
believes have positive return potential relative to other U.S. equities. Some of these methods evaluate individual companies or groups
of companies based on the ratio of their security price to historical financial information and forecasted financial information, such
as return on invested capital, profitability, cash flow and earnings, and a comparison of these ratios to current and historical averages.
Other methods
focus on patterns of information, such as price movement or volatility
of an asset class, security, or market, and macroeconomic factors. In constructing the Fund’s portfolio, GMO also considers position
size, sector and industry exposure, market capitalization, liquidity, and transaction costs. At times, the Fund may have substantial exposure
to a single asset class, industry, sector and companies with similar market capitalizations. The Fund may invest in securities of companies
of any market capitalization. GMO also may consider ESG (environmental, social and governance) criteria. For example, GMO generally avoids
investing the Fund’s assets in companies engaged in the manufacture, supply, or distribution of cluster munitions, as well as companies
primarily involved in the mining and production of thermal coal. The factors GMO considers and investment methods GMO uses can change
over time.
As an alternative to investing directly
in equities, the Fund may invest in exchange-traded and over-the-counter (OTC) derivatives and exchange-traded funds (ETFs). The Fund
also may invest in derivatives and ETFs in an attempt to obtain or adjust elements of its long or short investment exposure. Derivatives
used may include futures, options, and swap contracts. In addition, the Fund may lend its portfolio securities.
Under
normal circumstances, the Fund invests directly and indirectly (e.g., through underlying funds or derivatives) at least 80% of its assets
in equities tied economically to the United States (see “Name Policies”).
The Fund also may invest in U.S. Treasury
Fund, in money market funds unaffiliated with GMO, and directly in the types of investments typically held by money market funds.
The Fund’s ETF Class operates
as an actively managed exchange-traded fund (“ETF”).
|
||||||
| Rule 35d-1 Eighty Percent Investment Policy [Text Block] | fnd_NmRule35d1EightyPctInvstmntPlcyTextBlock | Under normal circumstances, the Fund invests directly and indirectly (e.g., through underlying funds or derivatives) at least 80% of its assets in equities tied economically to the United States (see “Name Policies”). | ||||||
| Bar Chart and Performance Table [Heading] | oef_BarChartAndPerformanceTableHeading | Performance | ||||||
| Performance Narrative [Text Block] | oef_PerformanceNarrativeTextBlock |
The
bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s annual
total returns from year to year for the periods indicated and by comparing the Fund’s average annual total returns for different
calendar periods with those of a broad-based securities market index. The
Fund’s ETF Class shares are a new class and, as of the date of this Prospectus, had not commenced operations. Returns
shown are those of Class III shares of the Fund, a mutual fund class of shares of the Fund not offered in this Prospectus, and have
not been adjusted to reflect the fees and expenses attributable to ETF Class shares. Class III shares would have substantially
similar annual returns to ETF Class shares because the shares are invested in the same portfolio of securities, and the annual returns
at NAV (assuming ETF Class shares are bought and sold without any premium or discount) would differ only to the extent that Class III
shares do not have the same expenses as ETF Class shares. Share classes that bear higher expenses than the share classes shown below would
have lower returns. 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 your tax situation
and may differ from those shown. After-tax returns shown are not relevant if you are tax-exempt or if you hold your Fund shares through
tax-advantaged arrangements (such as a 401(k) plan or individual retirement account). After-tax
returns are shown for Class III shares only; after-tax returns for other classes will vary. Updated performance information
for the Fund is available at https://www.gmo.com/americas/investment-capabilities/etfs/.
Past performance (before and after taxes) is not an indication
of future performance.
|
||||||
| Performance Information Illustrates Variability of Returns [Text] | oef_PerformanceInformationIllustratesVariabilityOfReturns | The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s annual total returns from year to year for the periods indicated and by comparing the Fund’s average annual total returns for different calendar periods with those of a broad-based securities market index. | ||||||
| Performance One Year or Less [Text] | oef_PerformanceOneYearOrLess | The Fund’s ETF Class shares are a new class and, as of the date of this Prospectus, had not commenced operations. | ||||||
| Performance Availability Website Address [Text] | oef_PerformanceAvailabilityWebSiteAddress | https://www.gmo.com/americas/investment-capabilities/etfs/ | ||||||
| Performance Past Does Not Indicate Future [Text] | oef_PerformancePastDoesNotIndicateFuture | Past performance (before and after taxes) is not an indication of future performance. | ||||||
| Bar Chart [Heading] | oef_BarChartHeading | Annual Total Returns/Class III Shares1 Years Ending December 31 | ||||||
| Bar Chart Footnotes [Text Block] | oef_BarChartFootnotesTextBlock | The Fund is the successor to GMO U.S. Core Fund, a former series of GMO Trust that had an investment objective and investment policies and restrictions substantially identical to those of the Fund. Performance of the Fund through September 16, 2005 is that of GMO U.S. Core Fund and reflects GMO U.S. Core Fund’s annual operating expenses (0.02% higher than those of the Fund). |
||||||
| Bar Chart Closing [Text Block] | oef_BarChartClosingTextBlock |
Highest
Quarter: 19.81%
2Q 2020
Lowest Quarter: -21.15% 1Q 2020 Year-to-Date: 14.57% As of 6/30/2026 |
||||||
| Year to Date Return, Label [Optional Text] | oef_YearToDateReturnLabel | Year-to-Date: | ||||||
| Bar Chart, Year to Date Return, Date | oef_BarChartYearToDateReturnDate | Jun. 30, 2026 | ||||||
| Bar Chart, Year to Date Return | oef_BarChartYearToDateReturn | 14.57% | ||||||
| Highest Quarterly Return, Label [Optional Text] | oef_HighestQuarterlyReturnLabel | Highest Quarter: | ||||||
| Highest Quarterly Return, Date | oef_BarChartHighestQuarterlyReturnDate | Jun. 30, 2020 | ||||||
| Highest Quarterly Return | oef_BarChartHighestQuarterlyReturn | 19.81% | ||||||
| Lowest Quarterly Return, Label [Optional Text] | oef_LowestQuarterlyReturnLabel | Lowest Quarter: | ||||||
| Lowest Quarterly Return, Date | oef_BarChartLowestQuarterlyReturnDate | Mar. 31, 2020 | ||||||
| Lowest Quarterly Return | oef_BarChartLowestQuarterlyReturn | (21.15%) | ||||||
| Performance Table Heading | oef_PerformanceTableHeading | Average Annual Total Returns1 Periods Ending December 31, 2025 | ||||||
| Index No Deduction for Fees, Expenses, or Taxes [Text] | oef_IndexNoDeductionForFeesExpensesTaxes | (returns reflect no deduction for fees, expenses, or taxes) | ||||||
| Performance Table Uses Highest Federal Rate | oef_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 | oef_PerformanceTableNotRelevantToTaxDeferred | Actual after-tax returns depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant if you are tax-exempt or if you hold your Fund shares through tax-advantaged arrangements (such as a 401(k) plan or individual retirement account). | ||||||
| Performance Table One Class of after Tax Shown [Text] | oef_PerformanceTableOneClassOfAfterTaxShown | After-tax returns are shown for Class III shares only; after-tax returns for other classes will vary. | ||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Risk Lose Money [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock | Many factors can affect this value, and you may lose money by investing in the Fund. | ||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Risk Not Insured [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock | An investment in the Fund is not a bank deposit and is not insured or guaranteed by the FDIC or any government agency. | ||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Market Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Market
Risk – Equities − The market price of an equity in the Fund’s portfolio may decline due to factors
affecting the issuer or its industry or the economy and equity markets generally. If the Fund purchases an equity for less than its fundamental
fair (or intrinsic) value as assessed by GMO, the Fund runs the risk that the market price of the equity will not appreciate or will decline
(for example, if GMO’s assessment proves to be incorrect or the market fails to recognize the equity’s intrinsic value).
The Fund also may purchase equities that typically trade at higher multiples of current earnings than other securities, and the market
prices of these equities often are more sensitive to changes in future earnings expectations and interest rates than the market prices
of equities trading at lower multiples. Declines in stock market prices generally are likely to reduce the net asset value of the Fund’s
shares.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Management and Operational Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Management
and Operational Risk − The Fund runs the risk that GMO’s investment techniques will fail to produce intended results.
GMO uses quantitative models as part of its investment process. GMO’s models may not accurately predict future market movements.
In addition, GMO’s models rely on assumptions and data that are subject to limitations (e.g., inaccuracies, staleness) that could
adversely affect their predictive value. The Fund also runs the risk that GMO’s assessment of an investment, including a security’s
fundamental fair (or intrinsic) value, is wrong or that deficiencies in GMO’s or another service provider’s internal systems
or controls will cause losses for the Fund or impair Fund operations.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Market Disruption and Geopolitical Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Market
Disruption and Geopolitical Risk − Geopolitical and other events (e.g., wars, pandemics, sanctions, terrorism, diplomatic
tensions, dramatic changes in regulatory and/or foreign policy, cyberattacks, and rapid technological developments such as artificial
intelligence) often disrupt securities markets and adversely affect the general economy or particular economies and markets. Those events,
as well as other changes in non-U.S. and U.S. economic and political conditions, could exacerbate other risks or otherwise reduce the
value of the Fund’s investments.
|
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| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Focused Investment Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Focused
Investment Risk − Investments in countries, regions, asset classes, sectors, industries, currencies, or issuers that are
subject to the same or similar risk factors and investments whose market prices are closely correlated are subject to higher overall risk
than investments that are more diversified or whose market prices are not as closely correlated.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Smaller Company Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Smaller
Company Risk − Smaller companies may have limited product lines, markets, or financial resources, lack the competitive strength
of larger companies, have less experienced managers or depend on a few key employees. The securities of companies with smaller market
capitalizations often are less widely held and trade less frequently and in lesser quantities, and their market prices often fluctuate
more, than the securities of companies with larger market capitalizations.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Illiquidity Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Illiquidity
Risk − Low trading volume, lack of a market maker, large position size, or legal restrictions increase the risk that the
Fund or an underlying fund is limited or prevented from selling particular securities or closing derivative positions at desirable prices
at a particular time or at all.
|
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| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Derivatives and Short Sales Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Derivatives
and Short Sales Risk − The use of derivatives involves the risk that their value may not change as expected relative to
changes in the value of the underlying assets, pools of assets, rates, currencies or indices. Derivatives also present other risks, including
market risk, illiquidity risk, currency risk, credit risk, leveraging risk, commodities risk and counterparty risk. The market price of
an option is affected
by many factors, including changes in the market prices
or dividend rates of underlying securities (or in the case of indices, the securities in such indices); the time remaining before expiration;
changes in interest rates or exchange rates; and changes in the actual or perceived volatility of the relevant index or underlying securities.
The Fund typically creates short investment exposure by selling securities short or by taking a derivative position in which the value
of the derivative moves in the opposite direction from the price of an underlying asset, pool of assets, rate, currency or index. Specifically,
the net asset value of the Fund’s shares will be adversely affected if the securities or other assets that are the subject of the
Fund’s short exposures appreciate in value. The risk of loss associated with derivatives that provide short investment exposure
and short sales of securities is theoretically unlimited.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Counterparty Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Counterparty
Risk − The Fund runs the risk that the counterparty to a derivatives contract or a clearing member used by the Fund to hold
a cleared derivatives contract is unable or unwilling to make timely settlement payments, return the Fund’s collateral or otherwise
honor its obligations.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Leveraging Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Leveraging
Risk − The use of derivatives, short sales and securities lending can create leverage. Leverage increases the Fund’s
losses when the value of its investments (including derivatives) declines. In addition, the Fund’s portfolio will be leveraged
if it exercises its right to delay payment on a redemption and the value of the Fund’s assets declines between the time a redemption
request is treated as being received by the Fund and the time the Fund liquidates assets to fund that redemption.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | Large Transactions Risk [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
Large
Transactions Risk − To the extent that a large number of shares of the Fund is held by a single shareholder (e.g., an institutional
investor or another GMO Fund) or a group of shareholders with a common investment strategy (e.g., GMO asset allocation accounts), the
Fund is subject to the risk that a redemption by (or caused by) that shareholder or group will require the Fund to sell investments at
disadvantageous prices, disrupt the Fund’s operations, lead to temporary overexposure to the Fund’s intended investment
program or force the Fund’s liquidation. The Fund also may be subject to these effects when a number of shareholders collectively
redeem or sell a large amount of Fund shares.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | ETF Risks [Member] | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Risk [Text Block] | oef_RiskTextBlock |
ETF
Risks − The Fund’s ETF Class operates as an ETF and, as a result of this structure, ETF Class shares are exposed
to the following risks:
•
Costs
of Buying or Selling Shares Risk. Due to the costs of buying or selling the Fund’s ETF Class shares, including
brokerage commissions imposed by brokers and the variance in bid-ask spreads, frequent trading of ETF Class shares may significantly reduce
investment results and an investment in ETF Class shares may not be advisable for investors who anticipate regularly making small investments.
•
Limited
Authorized Participants, Market Makers and Liquidity Providers Risk. Because the Fund’s ETF Class operates
as an ETF, typically only a limited number of institutional investors (known as “Authorized Participants”) are authorized
to purchase and redeem shares ETF Class shares directly from the Fund. Retail investors cannot transact in ETF Class shares directly with
the Fund. In addition, there may be a limited number of market makers and/or liquidity providers in the marketplace to transact in ETF
Class shares, there may be demand for ETF Class shares, thereby increasing the market price above net asset value (“NAV”),
or lack of demand, which may decrease the market price below NAV, or in stressed market conditions, the market for ETF Class shares may
become less liquid in response to deteriorating liquidity in the markets for the Fund’s underlying portfolio holdings. As a result
of these considerations, ETF Class shares may trade at a material premium or discount to their NAV or these factors may, in turn, lead
to wider spreads between the bid and ask price of ETF Class shares. In addition, the ETF Class shares may face possible delisting if:
(i) Authorized Participants exit the business or otherwise become unable to process creation and/or redemption orders and no other
Authorized Participants step forward to perform these services, or (ii) market makers and/or liquidity providers exit the business
or significantly reduce their business activities and no other entities step forward to perform their functions.
•
Trading
Risk. The Fund’s ETF Class shares may trade on the NYSE Arca, Inc. (the “Exchange”) above
(premium) or below (discount) their NAV. In stressed market conditions, the market for ETF Class shares may become less liquid in response
to deteriorating liquidity in the markets for the Fund’s underlying portfolio holdings, which may increase the variance between
the market price of the ETF Class shares and the value of the Fund’s underlying holdings attributable to ETF Class shares. This
can be reflected as a spread between the bid and ask prices for the ETF Class shares quoted during the day or a premium or discount in
the closing price from their NAV. In addition, although the Fund’s ETF Class shares are currently listed on the Exchange, there
can be no assurance that an active trading market for ETF Class shares will develop or be maintained. Trading in ETF Class shares may
be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in ETF Class shares of the Fund inadvisable.
•
Cash
Transactions Risk. The Fund may effect some of its creations and redemptions of ETF Class shares for cash, rather
than in-kind securities. As a result, the Fund may have to sell portfolio securities at inopportune times in order to obtain the cash
needed to meet redemption orders. This may cause the Fund to sell a security and recognize ordinary income, or a capital gain or loss
that might not have been incurred if it had made a redemption in-kind. The use of cash creations and redemptions may also cause the Fund’s
ETF Class shares to trade in the market at wider bid-ask spreads or greater premiums or discounts to their NAV. In effecting creations
and redemptions in ETF Class shares in exchange for cash, the Fund may incur certain costs, including brokerage costs in connection with
investing cash received and may recognize capital gains in connection with cash redemptions, unlike an ETF that effects creations and
redemptions only in-kind. In addition, costs could be imposed on the Fund which would have the effect of decreasing the Fund’s
NAV to the extent the costs are not offset by a transaction fee payable by an Authorized Participant.
•
National Closed Market Trading
Risk. To the extent that the underlying securities or other instruments held by the Fund trade on foreign exchanges
or in foreign markets that may be closed when the securities exchange on which the Fund’s ETF Class shares trade is open, there
are likely to be deviations between the current price of such an underlying security and the last quoted price for the underlying security
(i.e., the Fund’s quote from the closed foreign market). The impact of a closed foreign market on the Fund is likely to be greater
where a large portion of the Fund’s underlying securities or other instruments trade on that closed foreign market or when the
foreign market is closed for unscheduled reasons. These deviations could result in premiums or discounts to the NAV of the Fund’s
ETF Class shares that may be greater than those experienced by other ETFs.
|
||||||
| GMO U.S. Equity Fund | GMO U.S. Equity Fund | ETF Class | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Management Fees (as a percentage of Assets) | oef_ManagementFeesOverAssets | 0.46% | [1] | |||||
| Distribution and Service (12b-1) Fees | oef_DistributionAndService12b1FeesOverAssets | 0.00% | ||||||
| Other Expenses (as a percentage of Assets): | oef_OtherExpensesOverAssets | 0.24% | [2] | |||||
| Expenses (as a percentage of Assets) | oef_ExpensesOverAssets | 0.70% | ||||||
| Fee Waiver or Reimbursement | oef_FeeWaiverOrReimbursementOverAssets | (0.21%) | [1] | |||||
| Net Expenses (as a percentage of Assets) | oef_NetExpensesOverAssets | 0.49% | ||||||
| Expense Example, with Redemption, 1 Year | oef_ExpenseExampleYear01 | $ 50 | ||||||
| Expense Example, with Redemption, 3 Years | oef_ExpenseExampleYear03 | 203 | ||||||
| Expense Example, with Redemption, 5 Years | oef_ExpenseExampleYear05 | 359 | ||||||
| Expense Example, with Redemption, 10 Years | oef_ExpenseExampleYear10 | $ 851 | ||||||
| GMO U.S. Equity Fund | S&P Composite 1500 Index (returns reflect no deduction for fees, expenses, or taxes) | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 17.02% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 13.96% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 14.46% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | [3] | ||||||
| GMO U.S. Equity Fund | Class III | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 13.58% | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 18.46% | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | (9.78%) | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 28.57% | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 13.69% | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 32.13% | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | (12.44%) | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 21.88% | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 20.92% | ||||||
| Annual Return [Percent] | oef_AnnlRtrPct | 22.22% | ||||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 22.22% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 15.82% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 13.97% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 11.65% | [3] | |||||
| Performance Inception Date | oef_PerfInceptionDate | Sep. 18, 1985 | ||||||
| GMO U.S. Equity Fund | Class III | After Taxes on Distributions | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 18.89% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 11.86% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 10.31% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 8.78% | [3] | |||||
| GMO U.S. Equity Fund | Class III | After Taxes on Distributions and Sales | ||||||||
| Prospectus [Line Items] | oef_ProspectusLineItems | |||||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 15.20% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 11.51% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 10.19% | [3] | |||||
| Average Annual Return, Percent | oef_AvgAnnlRtrPct | 8.76% | [3] | |||||
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