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Label

Element

Value

Risk/Return:

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Registrant Name

dei_EntityRegistrantName

GMO TRUST

Prospectus Date

rr_ProspectusDate

Jun. 30, 2018

GMO Special Opportunities Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

GMO SPECIAL OPPORTUNITIES FUND

Objective [Heading]

rr_ObjectiveHeading

Investment objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Positive total return.

Expense [Heading]

rr_ExpenseHeading

Fees and expenses

Expense Narrative [Text Block]

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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 (including the accounts of the Fund’s wholly-owned subsidiary, GMO Special Opportunities SPC Ltd., and excluding short-term investments) was 10% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

10.00%

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 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:

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

GMO generally uses fundamental analysis to identify investments that are, in GMO's judgment, trading below their fundamental fair (or intrinsic) value. GMO does not manage the Fund to, or control the Fund's risk relative to, any securities index or securities benchmark.

The factors GMO considers and investment methods GMO uses can change over time. The Fund may have long or short exposure to:

• non-U.S. and U.S. equities, which may include emerging country equities and equities of any market capitalization,

• non-U.S. and U.S. fixed income investments, such as asset-backed securities and other fixed income investments of any maturity, duration, or credit quality, including those that are below investment grade (commonly referred to as "junk bonds") and distressed and defaulted debt securities,

• currencies, and,

• from time to time, alternative instruments (e.g., instruments that seek exposure to, or reduce risks of, market volatility).

The Fund may engage in merger arbitrage.

The Fund is not restricted in its exposure to any particular issuer, asset class or market and at times may have substantial exposure (long or short) to a single issuer, asset class (e.g., equities or fixed income investments) or market, or to securities of companies in a particular country or type of country (e.g., emerging countries). GMO expects that the Fund's portfolio will consist of a limited number of investments. The Fund could be subject to material losses from a single investment. As of May 31, 2018, excluding cash and cash equivalents, and aggregating certain swap contracts, the Fund held 17 investments.

In pursuing its investment objective, the Fund may invest in a wide variety of exchange-traded and over-the-counter (OTC) derivatives, including, without limitation, reverse repurchase agreements, options, futures, swap contracts (such as total return swaps, interest rate swaps, credit default swaps, and other types of swaps), swaptions, and foreign currency derivative transactions. In addition, 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. As a result of its derivative positions, the Fund may have gross investment exposures in excess of its net assets (i.e., the Fund may be 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 gains exposure to commodities and some other assets by investing through a wholly-owned subsidiary advised by GMO, which does not receive management or other fees for its services. The subsidiary invests primarily in commodity-related derivatives and fixed income investments but also may invest in any other investment in which the Fund is permitted to invest directly. References in this Prospectus to actions 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 but may do so indirectly through its subsidiary (or otherwise).

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.

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. References to investments include those held directly by the Fund and indirectly through the Fund's investments in its wholly-owned subsidiary and in any underlying funds in which it invests. 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, including those risks to which the Fund is exposed as a result of its investments in its wholly-owned subsidiary and in any underlying funds, see "Additional Information about the Funds' Investment Strategies, Risks, and Expenses" and "Description of Principal Risks."

• Management and Operational Risk – The Fund runs the risk that GMO's investment techniques will fail to produce desired results. 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.

• Market Risk – Equities – The market price of an equity 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 due to GMO's incorrect assessment. Because the Fund normally does not take temporary defensive positions, declines in stock market prices generally are likely to reduce the net asset value of the Fund's shares.

• 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. 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. Investments in distressed or defaulted or other low quality debt investments generally are considered speculative and may involve substantial risks not normally associated with investments in higher quality securities, including adverse business, financial or economic conditions that lead to payment defaults and insolvency proceedings on the part of their issuers. 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 to seek recovery. 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 investment or may be required to accept cash or instruments worth less than its original investment.

• 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).

• 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.

• 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 issuers, asset classes, market, sectors, industries, countries, or regions (or in sectors within a country or region) 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. Because the Fund typically holds a limited number of investments, it could be subject to material losses from a single investment.

• 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.

• 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.

• 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.

• 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.

• Commodities Risk – Commodity prices can be extremely volatile, and exposure to commodities can cause the value of the Fund's shares to decline or fluctuate in a rapid and unpredictable manner.

• 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.

• Small Company Risk – Smaller companies may have limited product lines, markets, or financial resources, lack the competitive strength of larger companies, have inexperienced 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.

• Merger Arbitrage Risk – If the Fund purchases securities in anticipation of a proposed merger, exchange offer, tender offer, or other similar transaction and that transaction later appears unlikely to be consummated or, in fact, is not consummated or is delayed, the market price of the securities purchased by the Fund is likely to decline sharply, resulting in losses to the Fund. The risk/reward payout of merger arbitrage strategies typically is asymmetric, with the losses in failed transactions often far exceeding the gains in successful transactions. Merger arbitrage strategies are subject to the risk of overall market movements, and the Fund may experience losses even if a transaction is consummated.

• Fund of Funds Risk – The Fund is indirectly exposed to all of the risks of an investment in its wholly-owned subsidiary and in any underlying funds in which it invests, including the risk that its wholly-owned subsidiary or 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.

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]

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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 Barclays U.S. Treasury Inflation Notes: 1-10 Years Index and the Consumer Price Index. 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). 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 Bloomberg Barclays U.S. Treasury Inflation Notes: 1-10 Years Index and the Consumer Price Index.

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 VI 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: 13.04% (2Q2017)
Lowest Quarter: -3.83% (3Q2015)
Year-to-Date (as of 3/31/18): 0.37%

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).

GMO Special Opportunities Fund | Class III

Risk/Return:

rr_RiskReturnAbstract

Purchase premium (as a percentage of amount invested)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

0.50%

Redemption fee (as a percentage of amount redeemed)

rr_RedemptionFeeOverRedemption

0.50%

rr_ManagementFeesOverAssets

1.10%

^[1]

Shareholder service fee

rr_DistributionOrSimilarNon12b1FeesOverAssets

0.15%

^[1]

rr_OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.30%

Expense reimbursement/waiver

rr_FeeWaiverOrReimbursementOverAssets

none

^[1]

Total annual fund operating expenses after expense reimbursement/waiver (Fund and underlying fund expenses)

rr_NetExpensesOverAssets

1.30%

rr_ExpenseExampleYear01

$ 233

rr_ExpenseExampleYear03

516

rr_ExpenseExampleYear05

819

rr_ExpenseExampleYear10

1,681

rr_ExpenseExampleNoRedemptionYear01

182

rr_ExpenseExampleNoRedemptionYear03

460

rr_ExpenseExampleNoRedemptionYear05

759

rr_ExpenseExampleNoRedemptionYear10

$ 1,610

GMO Special Opportunities Fund | Class IV

Risk/Return:

rr_RiskReturnAbstract

Purchase premium (as a percentage of amount invested)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

0.50%

Redemption fee (as a percentage of amount redeemed)

rr_RedemptionFeeOverRedemption

0.50%

rr_ManagementFeesOverAssets

1.10%

^[1]

Shareholder service fee

rr_DistributionOrSimilarNon12b1FeesOverAssets

0.10%

^[1]

rr_OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.25%

Expense reimbursement/waiver

rr_FeeWaiverOrReimbursementOverAssets

none

^[1]

Total annual fund operating expenses after expense reimbursement/waiver (Fund and underlying fund expenses)

rr_NetExpensesOverAssets

1.25%

rr_ExpenseExampleYear01

$ 228

rr_ExpenseExampleYear03

500

rr_ExpenseExampleYear05

793

rr_ExpenseExampleYear10

1,626

rr_ExpenseExampleNoRedemptionYear01

177

rr_ExpenseExampleNoRedemptionYear03

445

rr_ExpenseExampleNoRedemptionYear05

733

rr_ExpenseExampleNoRedemptionYear10

$ 1,554

GMO Special Opportunities Fund | Class V

Risk/Return:

rr_RiskReturnAbstract

Purchase premium (as a percentage of amount invested)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

0.50%

Redemption fee (as a percentage of amount redeemed)

rr_RedemptionFeeOverRedemption

0.50%

rr_ManagementFeesOverAssets

1.10%

^[1]

Shareholder service fee

rr_DistributionOrSimilarNon12b1FeesOverAssets

0.085%

^[1]

rr_OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.24%

Expense reimbursement/waiver

rr_FeeWaiverOrReimbursementOverAssets

none

^[1]

Total annual fund operating expenses after expense reimbursement/waiver (Fund and underlying fund expenses)

rr_NetExpensesOverAssets

1.24%

rr_ExpenseExampleYear01

$ 227

rr_ExpenseExampleYear03

497

rr_ExpenseExampleYear05

787

rr_ExpenseExampleYear10

1,614

rr_ExpenseExampleNoRedemptionYear01

176

rr_ExpenseExampleNoRedemptionYear03

441

rr_ExpenseExampleNoRedemptionYear05

728

rr_ExpenseExampleNoRedemptionYear10

$ 1,542

GMO Special Opportunities Fund | Class VI

Risk/Return:

rr_RiskReturnAbstract

Purchase premium (as a percentage of amount invested)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

0.50%

Redemption fee (as a percentage of amount redeemed)

rr_RedemptionFeeOverRedemption

0.50%

rr_ManagementFeesOverAssets

1.10%

^[1]

Shareholder service fee

rr_DistributionOrSimilarNon12b1FeesOverAssets

0.055%

^[1]

rr_OtherExpensesOverAssets

0.05%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.21%

Expense reimbursement/waiver

rr_FeeWaiverOrReimbursementOverAssets

none

^[1]

Total annual fund operating expenses after expense reimbursement/waiver (Fund and underlying fund expenses)

rr_NetExpensesOverAssets

1.21%

rr_ExpenseExampleYear01

$ 224

rr_ExpenseExampleYear03

488

rr_ExpenseExampleYear05

772

rr_ExpenseExampleYear10

1,581

rr_ExpenseExampleNoRedemptionYear01

173

rr_ExpenseExampleNoRedemptionYear03

432

rr_ExpenseExampleNoRedemptionYear05

712

rr_ExpenseExampleNoRedemptionYear10

$ 1,509

rr_AnnualReturn2015

2.25%

rr_AnnualReturn2016

4.61%

rr_AnnualReturn2017

32.23%

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

0.37%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2017

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

13.04%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(3.83%)

rr_AverageAnnualReturnYear01

30.91%

rr_AverageAnnualReturnYear05

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

9.66%

rr_AverageAnnualReturnInceptionDate

Jul. 28, 2014

GMO Special Opportunities Fund | Return After Taxes on Distributions | Class VI

Risk/Return:

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

27.46%

rr_AverageAnnualReturnYear05

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

8.18%

rr_AverageAnnualReturnInceptionDate

Jul. 28, 2014

GMO Special Opportunities Fund | Return After Taxes on Distributions and Sale of Fund Shares | Class VI

Risk/Return:

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

17.74%

rr_AverageAnnualReturnYear05

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

6.91%

rr_AverageAnnualReturnInceptionDate

Jul. 28, 2014

GMO Special Opportunities Fund | Bloomberg Barclays U.S. Treasury Inflation Notes: 1-10 Year Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

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

rr_IndexNoDeductionForFeesExpensesTaxes

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

rr_AverageAnnualReturnYear01

1.90%

rr_AverageAnnualReturnYear05

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

0.68%

rr_AverageAnnualReturnInceptionDate

Jul. 28, 2014

GMO Special Opportunities Fund | Consumer Price Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

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

rr_IndexNoDeductionForFeesExpensesTaxes

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

rr_AverageAnnualReturnYear01

2.03%

rr_AverageAnnualReturnYear05

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

1.22%

rr_AverageAnnualReturnInceptionDate

Jul. 28, 2014

[1]

Grantham, Mayo, Van Otterloo & Co. LLC ("GMO") has contractually agreed to reimburse the Fund for the portion of its "Specified Operating Expenses" (as defined below) that exceeds 0.10% 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, organizational and start-up expenses, federal securities law filing expenses, printing expenses, state and federal registration fees and custody expenses. GMO is permitted to recover from the Fund, on a class-by-class basis, "Specified Operating Expenses" it has borne or reimbursed (whether through reduction of its fees or otherwise) to the extent that the Fund's "Specified Operating Expenses" later fall below the annualized rate of 0.10% per year or the lower expense limit in effect when GMO seeks to recover the expenses. The Fund, however, is not obligated to pay any such amount more than three years after GMO bore or reimbursed an expense. Any such recovery will not cause the Fund to exceed the annual limitation rate set forth above or the lower expense limit as is in effect at the time GMO seeks to recover expenses. GMO also 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. These reimbursements and waivers 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.