Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	GMO TRUST
Prospectus Date	rr_ProspectusDate	Jun. 30, 2023
GMO Implementation Fund
Risk Return Abstract	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	GMO IMPLEMENTATION FUND
Objective [Heading]	rr_ObjectiveHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Investment objective</span>
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Positive total return, not relative return.
Expense [Heading]	rr_ExpenseHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Fees and expenses</span>
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The table below describes the fees and expenses that you may bear 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 [Text]	rr_OperatingExpensesCaption	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Annual Fund operating expenses</span> <br/><span style="color:#000000;font-family:Times New Roman;font-size:10pt;margin-left:0%;">(expenses that you bear each year as a percentage of the value of your investment)</span>
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	<span style="font-family:Times New Roman;font-size:8pt;font-style:italic;">June 30, 2024</span>
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Portfolio turnover</span>
Portfolio Turnover [Text Block]	rr_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, 2023, the Fund’s portfolio turnover rate (including the accounts of the Fund’s wholly-owned subsidiary, GMO Implementation SPC Ltd., and excluding short-term investments) was 125% 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, 2023 (including the accounts of GMO Implementation SPC Ltd., and excluding transactions in U.S. Treasury Fund and other short-term investments) was 118% of the average value of its portfolio securities.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	125.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Example</span>
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, regardless of whether or not you redeem 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 remain the same as those shown in the table. The one year amounts shown reflect the expense reimbursement noted in the expense table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading]	rr_StrategyHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Principal investment strategies</span>
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The investment strategies GMO pursues for the Fund are intended to complement the strategies it is pursuing for GMO Benchmark-Free Allocation Fund and other accounts it manages. Accordingly, the Fund is not intended to serve as a standalone investment.GMO uses its quantitative multi-year forecasts of returns among asset classes, together with its assessment of the relative risks of such asset classes, to determine the Fund’s strategic direction. An important component of those forecasts is GMO’s expectation that valuations ultimately revert to their fundamental fair (or intrinsic) value. The factors GMO considers and investment methods GMO uses can change over time.GMO does not manage the Fund to, or control the Fund’s risk relative to, any securities index or securities benchmark. Depending on GMO’s outlook, the Fund may have exposure to any asset class (e.g., non-U.S. equity, U.S. equity, emerging country equity, emerging country debt, non-U.S. fixed income, U.S. fixed income, real estate, and commodities) and at times may be substantially invested in a single asset class. The Fund may invest in securities of companies of any market capitalization. In addition, the Fund is not limited in its exposure to any particular market and may invest all of its assets in the securities of a limited number of companies in a single country and/or capitalization range. The Fund may invest a significant portion of its assets in the securities of companies in industries that are subject to the same or similar risk factors. To the extent the Fund invests in fixed income securities, it may have significant exposure to fixed income instruments of any credit quality, including those that are below investment grade (commonly referred to as “high yield” or “junk bonds”), and of any maturity or duration. The Fund also may make extensive use of short sales. GMO’s ability to shift investments among asset classes is not subject to any limits.The Fund may utilize an event-driven strategy, investing primarily in equity securities of companies that GMO expects to experience a material corporate event or catalyst in the relative short-term. To implement this strategy, the Fund may invest in derivatives or sell securities short in an effort to protect against market fluctuations or other risks or to adjust long or short investment exposure to one or more asset classes or issuers.As an alternative to investing directly in securities, the Fund may invest in exchange-traded and over-the-counter (OTC) derivatives (e.g., selling put options on securities) 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 options, futures, swap contracts, and reverse repurchase agreements. The Fund’s foreign currency exposure may differ from the currency exposure of its securities. The Fund may lend its portfolio securities.The Fund is not limited in its use of derivatives or in the total notional value of its derivative positions. Leverage is not a principal component of the Fund’s investment strategy. However, because of its derivative positions, the Fund may at times have gross investment exposure in excess of its net assets (i.e., the Fund may be leveraged), and therefore may be subject to higher risk of loss during those times than when the Fund is not leveraged. The Fund’s performance can depend substantially on the performance of assets or indices underlying its derivatives even though it does not own those assets or indices.The Fund gains exposure to commodities and some other asset classes by investing through a wholly-owned subsidiary advised by GMO, which does not receive management or other fees for its services to the subsidiary. The subsidiary invests primarily in commodity-related derivatives and fixed income instruments but also may invest in any other investment in which the Fund is permitted to invest directly. References in this Prospectus to action taken by the Fund refer to actions taken by the subsidiary as well as the Fund. The Fund does not invest directly in commodities and commodity-related derivatives.In seeking to achieve the Fund’s investment objective, GMO may invest a significant portion of the Fund’s net assets in cash and cash equivalents.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.
Risk [Heading]	rr_RiskHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Principal risks of investing in the Fund</span>
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Performance</span>
Performance Narrative [Text Block]	rr_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 the Bloomberg U.S. Treasury Inflation Notes: 1-10 Year Index and the Consumer Price Index. 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). Past performance (before and after taxes) is not an indication of future performance.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;margin-left:3.76%;">The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">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 the Bloomberg U.S. Treasury Inflation Notes: 1-10 Year Index and the Consumer Price Index.</span>
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;"> Past performance (before and after taxes) is not an indication of future performance.</span>
Bar Chart [Heading]	rr_BarChartHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Annual Total Returns</span> <br/><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Years Ending December 31</span>
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Highest Quarter:8.44%4Q 2022Lowest Quarter:-18.10%1Q 2020Year-to-Date:2.95%As of3/31/2023
Performance Table Heading	rr_PerformanceTableHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Average Annual Total Returns</span> <br/><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Periods Ending December 31, 2022</span>
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;"> After-tax </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.</span>
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;"> Actual after-tax returns depend on your tax situation and may differ from those shown. After-tax returns shown are not </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">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).</span>
GMO Implementation Fund | Risk Lose Money [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Many factors can affect this value, and you may lose money by investing in the Fund.
GMO Implementation Fund | Market Risk Equities [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_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 and GMO’s assessment proves to be incorrect, the Fund runs the risk that the market price of the equity will not appreciate or will decline. 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. When the Fund writes put options on a stock index, the value of those options will decline when the value of that index declines. The value of an index depends on the value of the equity securities in the index. Also, the Fund’s investment strategy of writing put options on stock indices can be expected to cause that strategy to underperform relative to those indices when the value of those indices rises sharply.
GMO Implementation Fund | Market Risk Fixed Income [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Market Risk – Fixed Income – The market price of a fixed income investment can decline due to market-related factors, including rising interest or inflation rates and widening credit spreads, or decreased liquidity due, for example, to market uncertainty about the value of a fixed income investment (or class of fixed income investments).
GMO Implementation Fund | Non-U.S. Investment Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Non-U.S. Investment Risk – The market prices of many non-U.S. securities fluctuate more than those of U.S. securities. Many non-U.S. securities markets are less stable, smaller, less liquid, and less regulated than U.S. securities markets, and the cost of trading in those markets often is higher than in U.S. securities markets. In addition, non-U.S. securities issuers often are not subject to as much regulation as U.S. issuers, and the reporting, recordkeeping, accounting, custody, and auditing standards to which those issuers are subject often are not as rigorous as U.S. standards. In addition, the Fund is subject to taxation by countries other than the United States, including potentially on a retroactive basis, on (i) capital gains it realizes or dividends, interest, or other amounts it realizes or accrues in respect of non-U.S. investments; (ii) transactions in those investments; and (iii) repatriation of proceeds generated from the sale or other disposition of those investments.Also, the Fund needs a license to invest directly in securities traded in many non-U.S. securities markets, and the Fund is subject to the risk that its license is terminated or suspended. In some non-U.S. securities markets, prevailing custody and trade settlement practices (e.g., the requirement to pay for securities prior to receipt) expose the Fund to credit and other risks. Further, adverse changes in investment regulations, capital requirements or exchange controls could adversely affect the value of the Fund’s investments. The risks above (such as substantial price fluctuations and market instability, illiquidity and lack of regulation) and other risks (e.g., nationalization, expropriation or other confiscation of assets of non-U.S. issuers, difficulties enforcing legal judgments or contractual rights and geopolitical risks) tend to be higher for investments in the securities of companies tied economically to emerging countries. The economies of emerging countries often depend predominantly on only a few industries or revenues from particular commodities and often are more volatile than the economies of developed countries.
GMO Implementation Fund | Management and Operational Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_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 Implementation Fund | Derivatives and Short Sales Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_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 equities 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 Implementation Fund | Illiquidity Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_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.
GMO Implementation Fund | Currency Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Currency Risk – Fluctuations in exchange rates can adversely affect the market value of the Fund’s foreign currency holdings and investments denominated in foreign currencies.
GMO Implementation Fund | Credit Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Credit Risk – The Fund runs the risk that the issuer or guarantor of a fixed income investment (including a sovereign or quasi-sovereign debt issuer) or the obligors of obligations underlying an asset-backed security will be unable or unwilling to satisfy their obligations to pay principal and interest or otherwise to honor their obligations in a timely manner or at all. The market price of a fixed income investment will normally decline as a result of the failure of an issuer, guarantor, or obligor to meet its payment obligations or in anticipation of such a failure. Below investment grade investments have speculative characteristics, and negative changes in economic conditions or other circumstances are more likely to impair the ability of issuers of those investments to make principal and interest payments than issuers of investment grade investments.In addition, investments in emerging country sovereign or quasi-sovereign debt are subject to a heightened risk that the issuer responsible for repayment of the debt may be unable or unwilling to pay interest and repay principal when due, and the Fund may lack recourse against the issuer in the event of a default. Investments in quasi-sovereign debt also are subject to the risk that the issuer will default independently of its sovereign.Investments in distressed or defaulted or other low quality debt investments generally are considered speculative and are subject to substantial risks not normally associated with investments in higher quality securities, including adverse business, financial or economic conditions that lead to their issuers’ payment defaults and insolvency proceedings. In particular, distressed or defaulted obligations might be repaid, if at all, only after lengthy workout or bankruptcy proceedings during which the issuer might not make any interest or other payments, and the Fund may incur additional expenses in its effort to be repaid. If GMO’s assessment of the eventual recovery value of a distressed or defaulted debt investment proves incorrect, the Fund may lose a substantial portion or all of its original investment or may be required to accept cash or instruments worth less than its original investment.
GMO Implementation Fund | Market Risk Asset Backed Securities [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Market Risk – Asset-Backed Securities – The market price of asset-backed securities, like that of other fixed income investments with complex structures, can decline for a variety of reasons, including investor uncertainty about their credit quality and the reliability of their payment streams. Payment streams associated with asset-backed securities held by the Fund depend on many factors (e.g., the cash flow generated by the assets backing the securities, deal structure, and creditworthiness of any credit-support provider), and a problem in any of these factors can lead to a reduction in the payment stream GMO expected the Fund to receive when the Fund purchased the asset-backed security. The liquidity of asset-backed securities (particularly below investment grade asset-backed securities) may change over time. During periods of deteriorating economic conditions, such as recessions, or periods of rising unemployment, delinquencies and losses generally increase, sometimes dramatically, for asset-backed securities whose underlying assets consist of loans, sales contracts, receivables and other obligations.
GMO Implementation Fund | Counterparty Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Counterparty Risk – The Fund runs the risk that the counterparty to a derivatives contract, a clearing member used by the Fund to hold a cleared derivatives contract, or a borrower of the Fund’s securities is unable or unwilling to make timely settlement payments, return the Fund’s collateral or otherwise honor its obligations.
GMO Implementation Fund | Focused Investment Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Focused Investment Risk – Investments focused 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 Implementation Fund | Leveraging Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_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 losses will result if the value of the Fund’s assets declines between the time a redemption request is deemed to be received by the Fund and the time the Fund liquidates assets to meet that request.
GMO Implementation Fund | Smaller Company Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_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 Implementation Fund | Market Disruption and Geopolitical Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Market Disruption and Geopolitical Risk – Geopolitical and other events (e.g., wars, pandemics, sanctions, terrorism) 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.
GMO Implementation Fund | Event-Driven Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Event-Driven Risk – If the Fund purchases securities in anticipation of a proposed merger, acquisition, exchange offer, tender offer, or other similar transaction and that transaction later appears likely to be delayed or unlikely to be consummated or, in fact, is not consummated or is delayed, the market price of the securities purchased by the Fund may decline sharply, resulting in losses to the Fund. The risk/reward payout of event-driven strategies (such as merger arbitrage) typically is asymmetric, with the losses in failed transactions often far exceeding the gains in successful transactions. Event-driven strategies are subject to the risk of overall market movements, and the Fund may experience losses even if a transaction is consummated.
GMO Implementation Fund | Commodities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Commodities Risk – Commodity prices can be extremely volatile, and exposure to commodities can cause the net asset value of the Fund’s shares to decline or fluctuate significantly.
GMO Implementation Fund | Large Shareholder Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Large Shareholder 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 that shareholder or group will require the Fund to sell securities at disadvantageous prices, disrupt the Fund’s operations, or force the Fund’s liquidation.
GMO Implementation Fund | Fund of Funds Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	•Fund of Funds Risk – The Fund is indirectly exposed to all of the risks of an investment in its wholly-owned subsidiary and in the underlying funds in which it invests, including the risk that its wholly-owned subsidiary and in those underlying funds will not perform as expected. The fees and expenses associated with an investment in the Fund are less predictable than those associated with an investment in funds that charge a fixed management fee.
GMO Implementation Fund | GMO Implementation Fund
Risk Return Abstract	rr_RiskReturnAbstract
Management fee	rr_ManagementFeesOverAssets	none
Dividend and interest expense on short sales	rr_Component1OtherExpensesOverAssets	0.36%
All other expenses	rr_Component3OtherExpensesOverAssets	0.08%
Total other expenses	rr_OtherExpensesOverAssets	0.44%	[1]
Total annual fund operating expenses	rr_ExpensesOverAssets	0.44%
Fee Waiver or Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.06%)	[2]
Total annual fund operating expenses after expense reimbursement/waiver	rr_NetExpensesOverAssets	0.38%
1 Year	rr_ExpenseExampleYear01	$ 39
3 Years	rr_ExpenseExampleYear03	135
5 Years	rr_ExpenseExampleYear05	240
10 Years	rr_ExpenseExampleYear10	$ 549
2013	rr_AnnualReturn2013	17.10%
2014	rr_AnnualReturn2014	2.21%
2015	rr_AnnualReturn2015	(4.63%)
2016	rr_AnnualReturn2016	3.56%
2017	rr_AnnualReturn2017	14.09%
2018	rr_AnnualReturn2018	(5.59%)
2019	rr_AnnualReturn2019	13.23%
2020	rr_AnnualReturn2020	(7.25%)
2021	rr_AnnualReturn2021	4.07%
2022	rr_AnnualReturn2022	(1.23%)
Year to Date Return, Label	rr_YearToDateReturnLabel	<span style="font-family:Times New Roman;font-size:10pt;">Year-to-Date:</span>
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Mar. 31, 2023
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	2.95%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	<span style="font-family:Times New Roman;font-size:10pt;">Highest Quarter:</span>
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2022
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	8.44%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	<span style="font-family:Times New Roman;font-size:10pt;">Lowest Quarter:</span>
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2020
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(18.10%)
1 Year	rr_AverageAnnualReturnYear01	(1.23%)
5 Years	rr_AverageAnnualReturnYear05	0.38%
10 Years	rr_AverageAnnualReturnYear10	3.23%
Incept.	rr_AverageAnnualReturnSinceInception	3.73%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2012
GMO Implementation Fund | Return After Taxes on Distributions | GMO Implementation Fund
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(2.22%)	[3]
5 Years	rr_AverageAnnualReturnYear05	(0.54%)	[3]
10 Years	rr_AverageAnnualReturnYear10	2.60%	[3]
Incept.	rr_AverageAnnualReturnSinceInception	3.14%	[3]
GMO Implementation Fund | Return After Taxes on Distributions and Sale of Shares | GMO Implementation Fund
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(0.30%)	[3]
5 Years	rr_AverageAnnualReturnYear05	0.19%	[3]
10 Years	rr_AverageAnnualReturnYear10	2.43%	[3]
Incept.	rr_AverageAnnualReturnSinceInception	2.86%	[3]
GMO Implementation Fund | Consumer Price Index (returns reflect no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	6.40%
5 Years	rr_AverageAnnualReturnYear05	3.75%
10 Years	rr_AverageAnnualReturnYear10	2.58%
Incept.	rr_AverageAnnualReturnSinceInception	2.49%
GMO Implementation Fund | Bloomberg U.S. Treasury Inflation Notes: 1-10 Year Index (returns reflect no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(7.34%)
5 Years	rr_AverageAnnualReturnYear05	2.50%
10 Years	rr_AverageAnnualReturnYear10	1.29%
Incept.	rr_AverageAnnualReturnSinceInception	1.49%

[1] The amount includes interest expense and borrowing costs for investments sold short, and dividend expenses incurred by the Fund as a result of short sales. “Other expenses” (before addition of interest expense and borrowing costs for investments sold short, and dividend expenses on short sales), interest expense and borrowing costs for investments sold short, and dividend expenses on short sales were approximately 0.07%, 0.04% and 0.33%, respectively. "Dividend and interest expense on short sales" reflects interest expense and dividends paid on borrowed securities. Dividends paid on borrowed securities are an expense of short sales. Such expenses are required to be treated as a Fund expense for accounting purposes and are not payable to Grantham, Mayo, Van Otterloo & Co. LLC (“GMO”).

[2] GMO has contractually agreed to reimburse the Fund for the portion of its “Specified Operating Expenses” (as defined below) that exceeds 0.01% of the Fund’s average daily net assets. “Specified Operating Expenses” means only the following expenses: audit expenses, fund accounting expenses, pricing service expenses, expenses of non-investment related tax services, transfer agency expenses, expenses of non-investment related legal services provided to the Fund by or at the direction of GMO, federal securities law filing expenses, printing expenses, state and federal registration fees, and custody expenses. This reimbursement will continue through at least June 30, 2024 and may not be terminated prior to this date without the action or consent of the Trust’s Board of Trustees.

[3] After-tax returns do not reflect distributions made by the Fund for all periods prior to July 1, 2015, the date on which the Fund elected to be treated as a corporation for U.S. federal income purposes. Further, as described in “Distributions and Taxes,” the Fund elected to be treated and intends to qualify and be treated each year as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended, for U.S. federal income tax purposes.