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Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

GMO TRUST

Prospectus Date

rr_ProspectusDate

Jun. 30, 2018

GMO Emerging Country Debt Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

GMO EMERGING COUNTRY DEBT FUND

Objective [Heading]

rr_ObjectiveHeading

Investment objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Total return in excess of that of its benchmark, the J.P. Morgan EMBI Global.

Expense [Heading]

rr_ExpenseHeading

Fees and expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The tables below describe the fees and expenses that you may bear for each class of shares if you buy and hold shares of the Fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder fees
(fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_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

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

June 30, 2019

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio turnover

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, when Fund shares are held in a taxable account, higher 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, 2018, the Fund’s portfolio turnover rate (excluding short-term investments) was 33% of the average value of its portfolio. 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, 2018, excluding transactions in U.S. Treasury Fund and other short-term investments, was 34% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

33.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

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. 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 waiver noted in the expense table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

If you sell your shares

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

If you do not sell your shares

Strategy [Heading]

rr_StrategyHeading

Principal investment strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund invests primarily in debt of emerging market sovereign or quasi-sovereign issuers that usually is denominated in U.S. dollars, Euros, Japanese yen, Swiss francs or British pounds sterling. "Sovereign" refers to a government and "quasi-sovereign" refers to a governmental agency, political subdivision or other instrumentality or issuer that is majority owned, directly or indirectly, or whose obligations are guaranteed, by a government. Under normal circumstances, the Fund invests directly and indirectly (e.g., through other GMO Funds or derivatives) at least 80% of its assets in debt investments tied economically to emerging countries (see "Name Policies"). In general, the Fund considers "emerging countries" to be countries that are included in the Fund's benchmark or that have similar national domestic products or default histories to those of countries included in the Fund's benchmark.

The Fund typically gains its investment exposure by purchasing debt investments or by using derivatives, typically credit default swaps. The Fund may invest in debt instruments of all credit qualities, including securities that are in default, and may invest in corporate bonds. (The debt instruments in which the Fund invests includes below investment grade debt investments, which are sometimes referred to as "junk bonds," although this term is not generally used to refer to emerging country debt securities.) Generally, at least 75% of the Fund's assets are denominated in, or hedged into, U.S. dollars. The Fund's performance is likely to be more volatile than that of its benchmark.

When constructing the portfolio, GMO considers risk at both the portfolio and individual security level and generally takes into account, among other factors, interest rate duration, credit spread duration, liquidity, transaction costs and default duration as well as the idiosyncratic risk of each instrument. When making investment decisions, GMO emphasizes its assessment of the risk-reward characteristics of the individual instruments in a given country over its outlook for that particular country. GMO uses fundamental analytical techniques as the basis for its analysis with respect to both individual instrument selection and country outlook. The factors GMO considers and investment methods GMO uses can change over time.

In pursuing its investment objective, the Fund typically invests in over-the-counter (OTC) derivatives, including options, swap contracts (in addition to credit default swaps), currency forwards (including currency forwards on currencies of developed markets), and reverse repurchase agreements. The Fund is not limited in its use of derivatives or in the total notional value of its derivative positions. As a result of its derivative positions, the Fund typically has gross investment exposures in excess of its net assets (i.e., the Fund typically is leveraged) and therefore is subject to heightened risk of loss. The Fund's performance can depend substantially, if not primarily, on the performance of assets or indices underlying its derivatives even though it does not own those assets or indices.

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.

GMO normally seeks to maintain an interest rate duration for the Fund that is similar to that of its benchmark (approximately 7.0 years as of 5/31/18). For an additional discussion of duration, see "Additional Information About the Funds' Investment Strategies, Risks, and Expenses — Bond Funds — Duration."

rr_RiskHeading

Principal risks of investing in the Fund

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

The value of the Fund's shares changes with the value of the Fund's investments. Many factors can affect this value, and you may lose money by investing in the Fund. The Fund is a non-diversified investment company under the Investment Company Act of 1940, as amended, and therefore a decline in the market price of a particular security held by the Fund may affect the Fund's performance more than if the Fund were a diversified investment company. The principal risks of investing in the Fund are summarized below. For a more complete discussion of these risks, see "Additional Information about the Funds' Investment Strategies, Risks, and Expenses" and "Description of Principal Risks."

• Credit Risk – The Fund runs the risk that the issuer or guarantor of a fixed income investment or the obligor of an obligation underlying an asset-backed security will be unable or unwilling to satisfy its obligation to pay principal and interest or otherwise to honor its obligations in a timely manner. The market price of a fixed income investment will normally decline as a result of the issuer's, guarantor's, or obligor's failure to meet its payment obligations or in anticipation of such failure. In addition, investments in emerging country sovereign or quasi-sovereign debt involve 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 default. Investments in quasi-sovereign debt also are subject to the risk that the issuer will default independently of its sovereign. Below investment grade investments have speculative characteristics, and 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.

• Market Risk – Fixed Income – The market price of a fixed income investment can decline due to market-related factors, including rising interest rates and widening credit spreads, or decreased liquidity due to market uncertainty about the value of a fixed income investment (or class of fixed income investments). In addition, the market prices of emerging country sovereign and quasi-sovereign debt instruments can decline due to uncertainty about their credit quality and the reliability of their payment streams.

• Illiquidity Risk – Low trading volume, lack of a market maker, large position size, or legal restrictions may limit or prevent the Fund from selling particular securities or closing derivative positions at desirable prices.

• 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, 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 stock market and underlying securities. The Fund may create short investment exposure 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. The risks of loss associated with derivatives that provide short investment exposure and short sales of securities are theoretically unlimited.

• 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 margin or otherwise honor its obligations.

• 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. Transactions in non-U.S. securities generally involve higher commission rates, transfer taxes, and custodial costs than similar transactions in U.S. securities. In addition, the Fund may be subject to non-U.S. taxes, 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 it could not invest if its license were 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. These and other risks (e.g., nationalization, expropriation or other confiscation of assets of non-U.S. issuers) tend to be greater for investments in the securities of companies tied economically to emerging countries, the economies of which may be predominantly based on only a few industries or dependent on revenues from particular commodities and of which often are more volatile than the economies of developed countries.

• 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 those shareholders of all or a large portion of their Fund shares will require the Fund to sell securities at disadvantageous prices or otherwise disrupt the Fund's operations.

• 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.

• Market Disruption and Geopolitical Risk – Geopolitical and other events may disrupt securities markets and adversely affect global economies and markets. Those events, as well as other changes in non-U.S. and U.S. economic and political conditions, could reduce the value of the Fund's investments.

• Focused Investment Risk – Investments focused in a limited number of asset classes, countries, regions, sectors, industries, or issuers that are subject to the same or similar risk factors and investments whose prices are closely correlated are subject to greater overall risk than investments that are more diversified or whose prices are not as closely correlated.

• Fund of Funds Risk – The Fund is indirectly exposed to all of the risks of an investment in the underlying funds in which it invests, including the risk that those underlying funds will not perform as expected. Because the Fund bears the fees and expenses of the underlying funds in which it invests, the increase in fees and expenses of an underlying fund or a reallocation of the Fund's investments to underlying funds with higher fees or expenses will increase the Fund's total expenses.

• 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 market 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, creditworthiness of any credit-support provider, and reliability of various other service providers with access to the payment stream), 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.

• Leveraging Risk – The use of derivatives and securities lending creates 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 redemption requests.

• Management and Operational Risk – The Fund runs the risk that GMO's investment techniques will fail to produce desired results. GMO uses quantitative models as part of its investment process. GMO's models may not accurately predict future market movements or characteristics. In addition, they are based on assumptions that can limit their effectiveness, and they rely on data that is 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Many factors can affect this value, and you may lose money by investing in the Fund.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The Fund is a non-diversified investment company under the Investment Company Act of 1940, as amended, and therefore a decline in the market price of a particular security held by the Fund may affect the Fund's performance more than if the Fund were a diversified investment company.

Bar Chart and Performance Table [Heading]

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Performance

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 Fund’s benchmark (which is a broad-based index) and a composite index computed by GMO. Purchase premiums and redemption fees are not reflected in the bar chart, but are reflected in the table; as a result, the returns in the table are lower than the returns in the bar chart. Returns in the table reflect current purchase premiums and redemption fees. 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 www.gmo.com. Past performance (before and after taxes) is not an indication of future performance.

Performance Information Illustrates Variability of Returns [Text]

rr_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 the Fund’s benchmark (which is a broad-based index) and a composite index computed by GMO.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.gmo.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

Past performance (before and after taxes) is not an indication of future performance.

Bar Chart [Heading]

rr_BarChartHeading

Annual Total Returns/Class III Shares
Years Ending December 31

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Purchase premiums and redemption fees are not reflected in the bar chart, but are reflected in the table; as a result, the returns in the table are lower than the returns in the bar chart.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Quarter: 20.29% (3Q2009)
Lowest Quarter: -23.39% (4Q2008)
Year-to-Date (as of 3/31/18): -1.17%

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns
Periods Ending December 31, 2017

Performance Table Does Reflect Sales Loads

rr_PerformanceTableDoesReflectSalesLoads

Returns in the table reflect current purchase premiums and redemption fees.

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

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]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax returns are shown for Class III shares only; after-tax returns for other classes will vary.

GMO Emerging Country Debt Fund | Class III

Risk/Return:

rr_RiskReturnAbstract

Purchase premium (as a percentage of amount invested)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

0.75%

Redemption fee (as a percentage of amount redeemed)

rr_RedemptionFeeOverRedemption

0.75%

rr_ManagementFeesOverAssets

0.35%

^[1]

Shareholder service fee

rr_DistributionOrSimilarNon12b1FeesOverAssets

0.15%

^[1]

rr_OtherExpensesOverAssets

0.03%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.53%

rr_FeeWaiverOrReimbursementOverAssets

none

^[1]

Total annual fund operating expenses after expense waiver

rr_NetExpensesOverAssets

0.53%

rr_ExpenseExampleYear01

$ 207

rr_ExpenseExampleYear03

329

rr_ExpenseExampleYear05

462

rr_ExpenseExampleYear10

850

rr_ExpenseExampleNoRedemptionYear01

129

rr_ExpenseExampleNoRedemptionYear03

244

rr_ExpenseExampleNoRedemptionYear05

369

rr_ExpenseExampleNoRedemptionYear10

$ 735

rr_AnnualReturn2008

(33.25%)

rr_AnnualReturn2009

50.17%

rr_AnnualReturn2010

25.64%

rr_AnnualReturn2011

7.50%

rr_AnnualReturn2012

26.73%

rr_AnnualReturn2013

(1.18%)

rr_AnnualReturn2014

5.98%

rr_AnnualReturn2015

0.02%

rr_AnnualReturn2016

13.86%

rr_AnnualReturn2017

12.48%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2018

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(1.17%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.29%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(23.39%)

rr_AverageAnnualReturnYear01

10.80%

rr_AverageAnnualReturnYear05

5.73%

rr_AverageAnnualReturnYear10

8.53%

Since Inception

rr_AverageAnnualReturnSinceInception

14.56%

rr_AverageAnnualReturnInceptionDate

Apr. 19, 1994

GMO Emerging Country Debt Fund | Class IV

Risk/Return:

rr_RiskReturnAbstract

Purchase premium (as a percentage of amount invested)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

0.75%

Redemption fee (as a percentage of amount redeemed)

rr_RedemptionFeeOverRedemption

0.75%

rr_ManagementFeesOverAssets

0.35%

^[1]

Shareholder service fee

rr_DistributionOrSimilarNon12b1FeesOverAssets

0.10%

^[1]

rr_OtherExpensesOverAssets

0.03%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.48%

rr_FeeWaiverOrReimbursementOverAssets

none

^[1]

Total annual fund operating expenses after expense waiver

rr_NetExpensesOverAssets

0.48%

rr_ExpenseExampleYear01

$ 202

rr_ExpenseExampleYear03

313

rr_ExpenseExampleYear05

434

rr_ExpenseExampleYear10

790

rr_ExpenseExampleNoRedemptionYear01

124

rr_ExpenseExampleNoRedemptionYear03

228

rr_ExpenseExampleNoRedemptionYear05

342

rr_ExpenseExampleNoRedemptionYear10

$ 674

rr_AverageAnnualReturnYear01

10.84%

rr_AverageAnnualReturnYear05

5.78%

rr_AverageAnnualReturnYear10

8.58%

Since Inception

rr_AverageAnnualReturnSinceInception

11.44%

rr_AverageAnnualReturnInceptionDate

Jan. 09, 1998

GMO Emerging Country Debt Fund | Return After Taxes on Distributions | Class III

Risk/Return:

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

7.56%

rr_AverageAnnualReturnYear05

2.54%

rr_AverageAnnualReturnYear10

4.99%

Since Inception

rr_AverageAnnualReturnSinceInception

9.29%

rr_AverageAnnualReturnInceptionDate

Apr. 19, 1994

GMO Emerging Country Debt Fund | Return After Taxes on Distributions and Sale of Fund Shares | Class III

Risk/Return:

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

6.10%

rr_AverageAnnualReturnYear05

2.84%

rr_AverageAnnualReturnYear10

5.01%

Since Inception

rr_AverageAnnualReturnSinceInception

9.30%

rr_AverageAnnualReturnInceptionDate

Apr. 19, 1994

GMO Emerging Country Debt Fund | J.P. Morgan EMBI Global (Fund benchmark) (reflects no deduction for fees, expenses, or taxes) | Class III

Risk/Return:

rr_RiskReturnAbstract

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses, or taxes)

rr_AverageAnnualReturnYear01

9.32%

rr_AverageAnnualReturnYear05

3.75%

rr_AverageAnnualReturnYear10

7.05%

Since Inception

rr_AverageAnnualReturnSinceInception

10.38%

rr_AverageAnnualReturnInceptionDate

Apr. 19, 1994

GMO Emerging Country Debt Fund | J.P. Morgan EMBI Global (Fund benchmark) (reflects no deduction for fees, expenses, or taxes) | Class IV

Risk/Return:

rr_RiskReturnAbstract

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses, or taxes)

rr_AverageAnnualReturnYear01

9.32%

rr_AverageAnnualReturnYear05

3.75%

rr_AverageAnnualReturnYear10

7.05%

Since Inception

rr_AverageAnnualReturnSinceInception

8.70%

rr_AverageAnnualReturnInceptionDate

Jan. 09, 1998

GMO Emerging Country Debt Fund | J.P. Morgan EMBI Global + (Composite index) | Class III

Risk/Return:

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

9.32%

rr_AverageAnnualReturnYear05

3.75%

rr_AverageAnnualReturnYear10

7.05%

Since Inception

rr_AverageAnnualReturnSinceInception

10.31%

rr_AverageAnnualReturnInceptionDate

Apr. 19, 1994

GMO Emerging Country Debt Fund | J.P. Morgan EMBI Global + (Composite index) | Class IV

Risk/Return:

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

9.32%

rr_AverageAnnualReturnYear05

3.75%

rr_AverageAnnualReturnYear10

7.05%

Since Inception

rr_AverageAnnualReturnSinceInception

8.63%

rr_AverageAnnualReturnInceptionDate

Jan. 09, 1998

[1]

Grantham, Mayo, Van Otterloo & Co. LLC ("GMO") has contractually agreed to waive or reduce the Fund's management fees and shareholder service fees to the extent necessary to offset the management fees and shareholder service fees paid to GMO that are directly or indirectly borne by the Fund or a class of shares of the Fund as a result of the Fund's direct or indirect investments in other series of GMO Trust ("GMO Funds"). Management fees and shareholder service fees will not be waived below zero. This waiver will continue through at least June 30, 2019, and may not be terminated prior to this date without the action or consent of the Trust's Board of Trustees. During the Fund's most recent fiscal year, the impact of this waiver was less than 0.01%.