You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

<span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 400; grid-area: auto; line-height: 13.3333px; margin: 0px; overflow: visible; text-align: left;">https://www.gmo.com/americas/mutual-fund-documents/</span>

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$39	0.77%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 39

Expense Ratio, Percent

0.77%

AssetsNet

$ 805,063,533

Holdings Count | Holding

101

InvestmentCompanyPortfolioTurnover

32.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$805,063,533
# of Portfolio Holdings	101
Portfolio Turnover Rate	32%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 62%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	50.6
France	11.0
South Korea	7.3
Canada	7.2
Japan	3.8
Finland	3.2
Germany	3.1
Spain	3.1
Chile	2.3
Mexico	2.0
Norway	1.5
Other (each less than 1%)	4.9

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213399

Shareholder Report [Line Items]

Fund Name

GMO Climate Change Fund

Class Name

Class R6

Trading Symbol

GCCAX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Climate Change Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$39	0.77%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 39

Expense Ratio, Percent

0.77%

AssetsNet

$ 805,063,533

Holdings Count | Holding

101

InvestmentCompanyPortfolioTurnover

32.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$805,063,533
# of Portfolio Holdings	101
Portfolio Turnover Rate	32%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 62%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	50.6
France	11.0
South Korea	7.3
Canada	7.2
Japan	3.8
Finland	3.2
Germany	3.1
Spain	3.1
Chile	2.3
Mexico	2.0
Norway	1.5
Other (each less than 1%)	4.9

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213398

Shareholder Report [Line Items]

Fund Name

GMO Climate Change Fund

Class Name

Class I

Trading Symbol

GCCLX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Climate Change Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$44	0.87%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 44

Expense Ratio, Percent

0.87%

AssetsNet

$ 805,063,533

Holdings Count | Holding

101

InvestmentCompanyPortfolioTurnover

32.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$805,063,533
# of Portfolio Holdings	101
Portfolio Turnover Rate	32%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 62%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	50.6
France	11.0
South Korea	7.3
Canada	7.2
Japan	3.8
Finland	3.2
Germany	3.1
Spain	3.1
Chile	2.3
Mexico	2.0
Norway	1.5
Other (each less than 1%)	4.9

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000228647

Shareholder Report [Line Items]

Fund Name

GMO Emerging Markets ex-China Fund

Class Name

Class III

Trading Symbol

GMAUX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Markets ex-China Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$42	0.81%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 42

Expense Ratio, Percent

0.81%

AssetsNet

$ 82,872,463

Holdings Count | Holding

296

InvestmentCompanyPortfolioTurnover

37.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$82,872,463
# of Portfolio Holdings	296
Portfolio Turnover Rate	37%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 47%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Taiwan	27.8
India	18.5
Brazil	12.7
South Korea	7.6
Indonesia	7.0
Mexico	6.4
South Africa	5.8
Hungary	3.9
Vietnam	2.4
Thailand	2.3
Colombia	1.0
Other (each less than 1%)	4.6

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000228643

Shareholder Report [Line Items]

Fund Name

GMO Emerging Markets ex-China Fund

Class Name

Class VI

Trading Symbol

GMAQX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Markets ex-China Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$36	0.68%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 36

Expense Ratio, Percent

0.68%

AssetsNet

$ 82,872,463

Holdings Count | Holding

296

InvestmentCompanyPortfolioTurnover

37.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$82,872,463
# of Portfolio Holdings	296
Portfolio Turnover Rate	37%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 47%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Taiwan	27.8
India	18.5
Brazil	12.7
South Korea	7.6
Indonesia	7.0
Mexico	6.4
South Africa	5.8
Hungary	3.9
Vietnam	2.4
Thailand	2.3
Colombia	1.0
Other (each less than 1%)	4.6

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000013268

Shareholder Report [Line Items]

Fund Name

GMO Emerging Markets Fund

Class Name

Class II

Trading Symbol

GMEMX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Markets Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class II	$54	1.03%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 54

Expense Ratio, Percent

1.03%

AssetsNet

$ 401,681,962

Holdings Count | Holding

361

InvestmentCompanyPortfolioTurnover

52.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$401,681,962
# of Portfolio Holdings	361
Portfolio Turnover Rate	52%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 61%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Taiwan	21.6
China	21.6
India	13.3
Brazil	11.9
Mexico	6.3
South Africa	4.4
Hungary	4.0
Indonesia	3.9
South Korea	3.8
Vietnam	2.4
Thailand	2.3
Other (each less than 1%)	4.5

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000013269

Shareholder Report [Line Items]

Fund Name

GMO Emerging Markets Fund

Class Name

Class III

Trading Symbol

GMOEX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Markets Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$50	0.97%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 50

Expense Ratio, Percent

0.97%

AssetsNet

$ 401,681,962

Holdings Count | Holding

361

InvestmentCompanyPortfolioTurnover

52.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$401,681,962
# of Portfolio Holdings	361
Portfolio Turnover Rate	52%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 61%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Taiwan	21.6
China	21.6
India	13.3
Brazil	11.9
Mexico	6.3
South Africa	4.4
Hungary	4.0
Indonesia	3.9
South Korea	3.8
Vietnam	2.4
Thailand	2.3
Other (each less than 1%)	4.5

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000013272

Shareholder Report [Line Items]

Fund Name

GMO Emerging Markets Fund

Class Name

Class VI

Trading Symbol

GEMMX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Markets Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$44	0.85%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 44

Expense Ratio, Percent

0.85%

AssetsNet

$ 401,681,962

Holdings Count | Holding

361

InvestmentCompanyPortfolioTurnover

52.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$401,681,962
# of Portfolio Holdings	361
Portfolio Turnover Rate	52%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 61%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Taiwan	21.6
China	21.6
India	13.3
Brazil	11.9
Mexico	6.3
South Africa	4.4
Hungary	4.0
Indonesia	3.9
South Korea	3.8
Vietnam	2.4
Thailand	2.3
Other (each less than 1%)	4.5

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213362

Shareholder Report [Line Items]

Fund Name

GMO Emerging Markets Fund

Class Name

Class R6

Trading Symbol

GEMNX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Markets Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$54	1.03%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 54

Expense Ratio, Percent

1.03%

AssetsNet

$ 401,681,962

Holdings Count | Holding

361

InvestmentCompanyPortfolioTurnover

52.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$401,681,962
# of Portfolio Holdings	361
Portfolio Turnover Rate	52%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 61%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Taiwan	21.6
China	21.6
India	13.3
Brazil	11.9
Mexico	6.3
South Africa	4.4
Hungary	4.0
Indonesia	3.9
South Korea	3.8
Vietnam	2.4
Thailand	2.3
Other (each less than 1%)	4.5

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213363

Shareholder Report [Line Items]

Fund Name

GMO Emerging Markets Fund

Class Name

Class I

Trading Symbol

GEMEX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Markets Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$57	1.10%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 57

Expense Ratio, Percent

1.10%

AssetsNet

$ 401,681,962

Holdings Count | Holding

361

InvestmentCompanyPortfolioTurnover

52.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$401,681,962
# of Portfolio Holdings	361
Portfolio Turnover Rate	52%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 61%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Taiwan	21.6
China	21.6
India	13.3
Brazil	11.9
Mexico	6.3
South Africa	4.4
Hungary	4.0
Indonesia	3.9
South Korea	3.8
Vietnam	2.4
Thailand	2.3
Other (each less than 1%)	4.5

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000011881

Shareholder Report [Line Items]

Fund Name

GMO International Equity Fund

Class Name

Class III

Trading Symbol

GMOIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Equity Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$36	0.67%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 36

Expense Ratio, Percent

0.67%

AssetsNet

$ 1,045,635,973

Holdings Count | Holding

217

InvestmentCompanyPortfolioTurnover

33.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,045,635,973
# of Portfolio Holdings	217
Portfolio Turnover Rate	33%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 36%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Japan	25.4
France	13.4
United Kingdom	11.4
Switzerland	6.3
Spain	6.2
United States	6.0
Netherlands	5.7
Italy	4.9
Germany	4.5
Australia	3.2
Singapore	3.0
Sweden	2.9
Norway	2.1
Belgium	1.8
Hong Kong	1.1
Other (each less than 1%)	2.1

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000011882

Shareholder Report [Line Items]

Fund Name

GMO International Equity Fund

Class Name

Class IV

Trading Symbol

GMCFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Equity Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$33	0.61%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 33

Expense Ratio, Percent

0.61%

AssetsNet

$ 1,045,635,973

Holdings Count | Holding

217

InvestmentCompanyPortfolioTurnover

33.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,045,635,973
# of Portfolio Holdings	217
Portfolio Turnover Rate	33%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 36%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Japan	25.4
France	13.4
United Kingdom	11.4
Switzerland	6.3
Spain	6.2
United States	6.0
Netherlands	5.7
Italy	4.9
Germany	4.5
Australia	3.2
Singapore	3.0
Sweden	2.9
Norway	2.1
Belgium	1.8
Hong Kong	1.1
Other (each less than 1%)	2.1

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213358

Shareholder Report [Line Items]

Fund Name

GMO International Equity Fund

Class Name

Class I

Trading Symbol

GMOUX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Equity Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$46	0.86%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 46

Expense Ratio, Percent

0.86%

AssetsNet

$ 1,045,635,973

Holdings Count | Holding

217

InvestmentCompanyPortfolioTurnover

33.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,045,635,973
# of Portfolio Holdings	217
Portfolio Turnover Rate	33%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 36%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Japan	25.4
France	13.4
United Kingdom	11.4
Switzerland	6.3
Spain	6.2
United States	6.0
Netherlands	5.7
Italy	4.9
Germany	4.5
Australia	3.2
Singapore	3.0
Sweden	2.9
Norway	2.1
Belgium	1.8
Hong Kong	1.1
Other (each less than 1%)	2.1

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000013282

Shareholder Report [Line Items]

Fund Name

GMO International Opportunistic Value Fund

Class Name

Class III

Trading Symbol

GTMIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$37	0.69%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 37

Expense Ratio, Percent

0.69%

AssetsNet

$ 424,047,044

Holdings Count | Holding

173

InvestmentCompanyPortfolioTurnover

18.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$424,047,044
# of Portfolio Holdings	173
Portfolio Turnover Rate	18%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 22%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Japan	18.6
Canada	12.5
France	12.4
United Kingdom	10.7
Switzerland	9.3
Netherlands	4.9
Germany	4.6
Australia	4.6
Spain	4.5
Italy	4.4
Hong Kong	3.2
Belgium	1.8
United States	1.5
Finland	1.4
Sweden	1.4
Singapore	1.3
Norway	1.1
Other (each less than 1%)	1.8

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000013283

Shareholder Report [Line Items]

Fund Name

GMO International Opportunistic Value Fund

Class Name

Class IV

Trading Symbol

GMAZX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$34	0.64%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 34

Expense Ratio, Percent

0.64%

AssetsNet

$ 424,047,044

Holdings Count | Holding

173

InvestmentCompanyPortfolioTurnover

18.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$424,047,044
# of Portfolio Holdings	173
Portfolio Turnover Rate	18%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 22%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Japan	18.6
Canada	12.5
France	12.4
United Kingdom	10.7
Switzerland	9.3
Netherlands	4.9
Germany	4.6
Australia	4.6
Spain	4.5
Italy	4.4
Hong Kong	3.2
Belgium	1.8
United States	1.5
Finland	1.4
Sweden	1.4
Singapore	1.3
Norway	1.1
Other (each less than 1%)	1.8

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213365

Shareholder Report [Line Items]

Fund Name

GMO International Opportunistic Value Fund

Class Name

Class R6

Trading Symbol

GMBCX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Opportunistic Value Fund for the period of April 8, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment^{Footnote Reference*}	Costs paid as a percentage of a $10,000 investment
Class R6	$28	0.69%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.
Footnote^*	For the period April 8, 2024 (commencement of operations for Class R6) through August 31, 2024. The costs would have been higher had the Class operated the full six month period.

Expenses Paid, Amount

$ 28

Expense Ratio, Percent

0.69%

AssetsNet

$ 424,047,044

Holdings Count | Holding

173

InvestmentCompanyPortfolioTurnover

18.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$424,047,044
# of Portfolio Holdings	173
Portfolio Turnover Rate	18%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 22%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Japan	18.6
Canada	12.5
France	12.4
United Kingdom	10.7
Switzerland	9.3
Netherlands	4.9
Germany	4.6
Australia	4.6
Spain	4.5
Italy	4.4
Hong Kong	3.2
Belgium	1.8
United States	1.5
Finland	1.4
Sweden	1.4
Singapore	1.3
Norway	1.1
Other (each less than 1%)	1.8

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213364

Shareholder Report [Line Items]

Fund Name

GMO International Opportunistic Value Fund

Class Name

Class I

Trading Symbol

IOVFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$44	0.83%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 44

Expense Ratio, Percent

0.83%

AssetsNet

$ 424,047,044

Holdings Count | Holding

173

InvestmentCompanyPortfolioTurnover

18.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$424,047,044
# of Portfolio Holdings	173
Portfolio Turnover Rate	18%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 22%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

Japan	18.6
Canada	12.5
France	12.4
United Kingdom	10.7
Switzerland	9.3
Netherlands	4.9
Germany	4.6
Australia	4.6
Spain	4.5
Italy	4.4
Hong Kong	3.2
Belgium	1.8
United States	1.5
Finland	1.4
Sweden	1.4
Singapore	1.3
Norway	1.1
Other (each less than 1%)	1.8

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000222625

Shareholder Report [Line Items]

Fund Name

GMO-Usonian Japan Value Creation Fund

Class Name

Class III

Trading Symbol

GMAKX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO-Usonian Japan Value Creation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$36	0.68%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 36

Expense Ratio, Percent

0.68%

AssetsNet

$ 188,900,946

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

10.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$188,900,946
# of Portfolio Holdings	36
Portfolio Turnover Rate	10%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 12%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Capital Goods	27.0
Technology Hardware & Equipment	9.6
Food, Beverage & Tobacco	8.9
Consumer Durables & Apparel	8.7
Banks	8.0
Materials	7.6
Automobiles & Components	7.1
Financial Services	5.7
Semiconductors & Semiconductor Equipment	5.1
Health Care Equipment & Services	4.2
Insurance	3.8
Software & Services	2.5
Transportation	1.8

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000222627

Shareholder Report [Line Items]

Fund Name

GMO-Usonian Japan Value Creation Fund

Class Name

Class VI

Trading Symbol

GMAHX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO-Usonian Japan Value Creation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$31	0.58%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 31

Expense Ratio, Percent

0.58%

AssetsNet

$ 188,900,946

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

10.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$188,900,946
# of Portfolio Holdings	36
Portfolio Turnover Rate	10%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 12%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Capital Goods	27.0
Technology Hardware & Equipment	9.6
Food, Beverage & Tobacco	8.9
Consumer Durables & Apparel	8.7
Banks	8.0
Materials	7.6
Automobiles & Components	7.1
Financial Services	5.7
Semiconductors & Semiconductor Equipment	5.1
Health Care Equipment & Services	4.2
Insurance	3.8
Software & Services	2.5
Transportation	1.8

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000222630

Shareholder Report [Line Items]

Fund Name

GMO-Usonian Japan Value Creation Fund

Class Name

Class I

Trading Symbol

GMIIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO-Usonian Japan Value Creation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$41	0.78%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 41

Expense Ratio, Percent

0.78%

AssetsNet

$ 188,900,946

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

10.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$188,900,946
# of Portfolio Holdings	36
Portfolio Turnover Rate	10%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 12%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Capital Goods	27.0
Technology Hardware & Equipment	9.6
Food, Beverage & Tobacco	8.9
Consumer Durables & Apparel	8.7
Banks	8.0
Materials	7.6
Automobiles & Components	7.1
Financial Services	5.7
Semiconductors & Semiconductor Equipment	5.1
Health Care Equipment & Services	4.2
Insurance	3.8
Software & Services	2.5
Transportation	1.8

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000220241

Shareholder Report [Line Items]

Fund Name

GMO Quality Cyclicals Fund

Class Name

Class VI

Trading Symbol

GMAEX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Quality Cyclicals Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$21	0.41%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 21

Expense Ratio, Percent

0.41%

AssetsNet

$ 78,494,014

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$78,494,014
# of Portfolio Holdings	49
Portfolio Turnover Rate	6%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 10%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	54.2
United Kingdom	12.8
Spain	6.9
Mexico	5.6
France	5.6
Canada	3.8
Germany	3.4
Ireland	2.8
Finland	1.9
Brazil	1.1
Other (each less than 1%)	1.9

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000220259

Shareholder Report [Line Items]

Fund Name

GMO Quality Cyclicals Fund

Class Name

Class I

Trading Symbol

GMAOX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Quality Cyclicals Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$32	0.61%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 32

Expense Ratio, Percent

0.61%

AssetsNet

$ 78,494,014

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$78,494,014
# of Portfolio Holdings	49
Portfolio Turnover Rate	6%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 10%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	54.2
United Kingdom	12.8
Spain	6.9
Mexico	5.6
France	5.6
Canada	3.8
Germany	3.4
Ireland	2.8
Finland	1.9
Brazil	1.1
Other (each less than 1%)	1.9

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000011437

Shareholder Report [Line Items]

Fund Name

GMO Quality Fund

Class Name

Class III

Trading Symbol

GQETX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$27	0.50%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 27

Expense Ratio, Percent

0.50%

AssetsNet

$ 10,790,081,394

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

7.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$10,790,081,394
# of Portfolio Holdings	44
Portfolio Turnover Rate	7%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 14%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	78.4
United Kingdom	7.2
France	4.0
Taiwan	3.5
Germany	3.4
Switzerland	2.8
Other (each less than 1%)	0.7

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000011438

Shareholder Report [Line Items]

Fund Name

GMO Quality Fund

Class Name

Class IV

Trading Symbol

GQEFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$24	0.46%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 24

Expense Ratio, Percent

0.46%

AssetsNet

$ 10,790,081,394

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

7.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$10,790,081,394
# of Portfolio Holdings	44
Portfolio Turnover Rate	7%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 14%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	78.4
United Kingdom	7.2
France	4.0
Taiwan	3.5
Germany	3.4
Switzerland	2.8
Other (each less than 1%)	0.7

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000011440

Shareholder Report [Line Items]

Fund Name

GMO Quality Fund

Class Name

Class VI

Trading Symbol

GQLOX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$22	0.41%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 22

Expense Ratio, Percent

0.41%

AssetsNet

$ 10,790,081,394

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

7.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$10,790,081,394
# of Portfolio Holdings	44
Portfolio Turnover Rate	7%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 14%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	78.4
United Kingdom	7.2
France	4.0
Taiwan	3.5
Germany	3.4
Switzerland	2.8
Other (each less than 1%)	0.7

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213357

Shareholder Report [Line Items]

Fund Name

GMO Quality Fund

Class Name

Class R6

Trading Symbol

GQESX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$27	0.50%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 27

Expense Ratio, Percent

0.50%

AssetsNet

$ 10,790,081,394

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

7.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$10,790,081,394
# of Portfolio Holdings	44
Portfolio Turnover Rate	7%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 14%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	78.4
United Kingdom	7.2
France	4.0
Taiwan	3.5
Germany	3.4
Switzerland	2.8
Other (each less than 1%)	0.7

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213356

Shareholder Report [Line Items]

Fund Name

GMO Quality Fund

Class Name

Class I

Trading Symbol

GQLIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$32	0.60%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 32

Expense Ratio, Percent

0.60%

AssetsNet

$ 10,790,081,394

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

7.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$10,790,081,394
# of Portfolio Holdings	44
Portfolio Turnover Rate	7%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 14%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	78.4
United Kingdom	7.2
France	4.0
Taiwan	3.5
Germany	3.4
Switzerland	2.8
Other (each less than 1%)	0.7

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000241005

Shareholder Report [Line Items]

Fund Name

GMO Resource Transition Fund

Class Name

Class VI

Trading Symbol

GMOYX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Resource Transition Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$44	0.86%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 44

Expense Ratio, Percent

0.86%

AssetsNet

$ 120,742,981

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

21.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$120,742,981
# of Portfolio Holdings	60
Portfolio Turnover Rate	21%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 26%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	41.6
Canada	14.3
Brazil	10.7
United Kingdom	8.1
Chile	3.6
Sweden	3.3
Mexico	3.0
Finland	2.9
France	2.7
Australia	2.5
South Africa	2.0
China	1.6
Spain	1.4
Other (each less than 1%)	2.3

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000107485

Shareholder Report [Line Items]

Fund Name

GMO Resources Fund

Class Name

Class III

Trading Symbol

GOFIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Resources Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$36	0.71%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 36

Expense Ratio, Percent

0.71%

AssetsNet

$ 2,143,520,366

Holdings Count | Holding

107

InvestmentCompanyPortfolioTurnover

19.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,143,520,366
# of Portfolio Holdings	107
Portfolio Turnover Rate	19%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 33%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	37.2
United Kingdom	12.8
Brazil	10.0
Canada	9.5
Mexico	4.3
Argentina	3.0
Portugal	2.8
Norway	2.5
Spain	2.2
Chile	2.1
Italy	2.1
Finland	1.9
Sweden	1.9
Australia	1.8
France	1.5
Austria	1.2
South Africa	1.2
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000107486

Shareholder Report [Line Items]

Fund Name

GMO Resources Fund

Class Name

Class IV

Trading Symbol

GOVIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Resources Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$34	0.66%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 34

Expense Ratio, Percent

0.66%

AssetsNet

$ 2,143,520,366

Holdings Count | Holding

107

InvestmentCompanyPortfolioTurnover

19.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,143,520,366
# of Portfolio Holdings	107
Portfolio Turnover Rate	19%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 33%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	37.2
United Kingdom	12.8
Brazil	10.0
Canada	9.5
Mexico	4.3
Argentina	3.0
Portugal	2.8
Norway	2.5
Spain	2.2
Chile	2.1
Italy	2.1
Finland	1.9
Sweden	1.9
Australia	1.8
France	1.5
Austria	1.2
South Africa	1.2
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000107488

Shareholder Report [Line Items]

Fund Name

GMO Resources Fund

Class Name

Class VI

Trading Symbol

GMOWX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Resources Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$32	0.62%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 32

Expense Ratio, Percent

0.62%

AssetsNet

$ 2,143,520,366

Holdings Count | Holding

107

InvestmentCompanyPortfolioTurnover

19.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,143,520,366
# of Portfolio Holdings	107
Portfolio Turnover Rate	19%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 33%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	37.2
United Kingdom	12.8
Brazil	10.0
Canada	9.5
Mexico	4.3
Argentina	3.0
Portugal	2.8
Norway	2.5
Spain	2.2
Chile	2.1
Italy	2.1
Finland	1.9
Sweden	1.9
Australia	1.8
France	1.5
Austria	1.2
South Africa	1.2
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213393

Shareholder Report [Line Items]

Fund Name

GMO Resources Fund

Class Name

Class R6

Trading Symbol

GAAHX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Resources Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$36	0.71%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 36

Expense Ratio, Percent

0.71%

AssetsNet

$ 2,143,520,366

Holdings Count | Holding

107

InvestmentCompanyPortfolioTurnover

19.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,143,520,366
# of Portfolio Holdings	107
Portfolio Turnover Rate	19%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 33%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	37.2
United Kingdom	12.8
Brazil	10.0
Canada	9.5
Mexico	4.3
Argentina	3.0
Portugal	2.8
Norway	2.5
Spain	2.2
Chile	2.1
Italy	2.1
Finland	1.9
Sweden	1.9
Australia	1.8
France	1.5
Austria	1.2
South Africa	1.2
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000213392

Shareholder Report [Line Items]

Fund Name

GMO Resources Fund

Class Name

Class I

Trading Symbol

GEACX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Resources Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$42	0.82%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 42

Expense Ratio, Percent

0.82%

AssetsNet

$ 2,143,520,366

Holdings Count | Holding

107

InvestmentCompanyPortfolioTurnover

19.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,143,520,366
# of Portfolio Holdings	107
Portfolio Turnover Rate	19%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 33%.

Holdings [Text Block]

Country/Region Summary^{Footnote Reference*}

% of Investments

United States	37.2
United Kingdom	12.8
Brazil	10.0
Canada	9.5
Mexico	4.3
Argentina	3.0
Portugal	2.8
Norway	2.5
Spain	2.2
Chile	2.1
Italy	2.1
Finland	1.9
Sweden	1.9
Australia	1.8
France	1.5
Austria	1.2
South Africa	1.2
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments and derivative financial instruments, if any.

C000238041

Shareholder Report [Line Items]

Fund Name

GMO Small Cap Quality Fund

Class Name

Class III

Trading Symbol

GMAWX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Small Cap Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$39	0.75%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 39

Expense Ratio, Percent

0.75%

AssetsNet

$ 398,659,474

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

20.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$398,659,474
# of Portfolio Holdings	43
Portfolio Turnover Rate	20%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 43%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Capital Goods	18.1
Financial Services	11.9
Semiconductors & Semiconductor Equipment	9.9
Consumer Durables & Apparel	8.3
Health Care Equipment & Services	7.1
Food, Beverage & Tobacco	6.8
Materials	6.2
Transportation	5.6
Technology Hardware & Equipment	5.1
Automobiles & Components	3.8
Media & Entertainment	3.8
Software & Services	3.6
Consumer Discretionary Distribution & Retail	2.6
Energy	2.1
Consumer Staples Distribution & Retail	2.1
Commercial & Professional Services	1.9
Consumer Services	1.1

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000238042

Shareholder Report [Line Items]

Fund Name

GMO Small Cap Quality Fund

Class Name

Class VI

Trading Symbol

GSBGX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Small Cap Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$34	0.66%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 34

Expense Ratio, Percent

0.66%

AssetsNet

$ 398,659,474

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

20.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$398,659,474
# of Portfolio Holdings	43
Portfolio Turnover Rate	20%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 43%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Capital Goods	18.1
Financial Services	11.9
Semiconductors & Semiconductor Equipment	9.9
Consumer Durables & Apparel	8.3
Health Care Equipment & Services	7.1
Food, Beverage & Tobacco	6.8
Materials	6.2
Transportation	5.6
Technology Hardware & Equipment	5.1
Automobiles & Components	3.8
Media & Entertainment	3.8
Software & Services	3.6
Consumer Discretionary Distribution & Retail	2.6
Energy	2.1
Consumer Staples Distribution & Retail	2.1
Commercial & Professional Services	1.9
Consumer Services	1.1

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000238039

Shareholder Report [Line Items]

Fund Name

GMO Small Cap Quality Fund

Class Name

Class I

Trading Symbol

GMAYX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Small Cap Quality Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$39	0.75%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 39

Expense Ratio, Percent

0.75%

AssetsNet

$ 398,659,474

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

20.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$398,659,474
# of Portfolio Holdings	43
Portfolio Turnover Rate	20%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 43%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Capital Goods	18.1
Financial Services	11.9
Semiconductors & Semiconductor Equipment	9.9
Consumer Durables & Apparel	8.3
Health Care Equipment & Services	7.1
Food, Beverage & Tobacco	6.8
Materials	6.2
Transportation	5.6
Technology Hardware & Equipment	5.1
Automobiles & Components	3.8
Media & Entertainment	3.8
Software & Services	3.6
Consumer Discretionary Distribution & Retail	2.6
Energy	2.1
Consumer Staples Distribution & Retail	2.1
Commercial & Professional Services	1.9
Consumer Services	1.1

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000011423

Shareholder Report [Line Items]

Fund Name

GMO U.S. Equity Fund

Class Name

Class III

Trading Symbol

GMUEX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Equity Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$26	0.49%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 26

Expense Ratio, Percent

0.49%

AssetsNet

$ 135,732,589

Holdings Count | Holding

169

InvestmentCompanyPortfolioTurnover

40.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$135,732,589
# of Portfolio Holdings	169
Portfolio Turnover Rate	40%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 43%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Semiconductors & Semiconductor Equipment	13.2
Financial Services	11.5
Technology Hardware & Equipment	10.9
Media & Entertainment	8.7
Software & Services	7.1
Consumer Discretionary Distribution & Retail	6.3
Pharmaceuticals, Biotechnology & Life Sciences	5.5
Consumer Durables & Apparel	5.2
Commercial & Professional Services	4.9
Capital Goods	4.0
Energy	3.8
Insurance	3.6
Banks	3.6
Automobiles & Components	2.5
Consumer Staples Distribution & Retail	2.2
Consumer Services	1.8
Health Care Equipment & Services	1.5
Transportation	1.4
Other (each less than 1%)	2.3

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000011426

Shareholder Report [Line Items]

Fund Name

GMO U.S. Equity Fund

Class Name

Class VI

Trading Symbol

GMCQX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Equity Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$21	0.39%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 21

Expense Ratio, Percent

0.39%

AssetsNet

$ 135,732,589

Holdings Count | Holding

169

InvestmentCompanyPortfolioTurnover

40.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$135,732,589
# of Portfolio Holdings	169
Portfolio Turnover Rate	40%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 43%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Semiconductors & Semiconductor Equipment	13.2
Financial Services	11.5
Technology Hardware & Equipment	10.9
Media & Entertainment	8.7
Software & Services	7.1
Consumer Discretionary Distribution & Retail	6.3
Pharmaceuticals, Biotechnology & Life Sciences	5.5
Consumer Durables & Apparel	5.2
Commercial & Professional Services	4.9
Capital Goods	4.0
Energy	3.8
Insurance	3.6
Banks	3.6
Automobiles & Components	2.5
Consumer Staples Distribution & Retail	2.2
Consumer Services	1.8
Health Care Equipment & Services	1.5
Transportation	1.4
Other (each less than 1%)	2.3

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000241007

Shareholder Report [Line Items]

Fund Name

GMO U.S. Opportunistic Value Fund

Class Name

Class III

Trading Symbol

PPADX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$26	0.49%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 26

Expense Ratio, Percent

0.49%

AssetsNet

$ 556,244,271

Holdings Count | Holding

149

InvestmentCompanyPortfolioTurnover

29.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$556,244,271
# of Portfolio Holdings	149
Portfolio Turnover Rate	29%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 31%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Financial Services	12.9
Pharmaceuticals, Biotechnology & Life Sciences	12.1
Banks	11.1
Media & Entertainment	10.4
Health Care Equipment & Services	8.1
Energy	8.0
Technology Hardware & Equipment	5.2
Food, Beverage & Tobacco	4.1
Software & Services	3.7
Consumer Discretionary Distribution & Retail	3.3
Consumer Durables & Apparel	3.1
Capital Goods	3.1
Materials	2.7
Automobiles & Components	2.6
Telecommunication Services	2.4
Semiconductors & Semiconductor Equipment	1.9
Insurance	1.8
Consumer Staples Distribution & Retail	1.5
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000241008

Shareholder Report [Line Items]

Fund Name

GMO U.S. Opportunistic Value Fund

Class Name

Class IV

Trading Symbol

GUSOX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$23	0.44%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 23

Expense Ratio, Percent

0.44%

AssetsNet

$ 556,244,271

Holdings Count | Holding

149

InvestmentCompanyPortfolioTurnover

29.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$556,244,271
# of Portfolio Holdings	149
Portfolio Turnover Rate	29%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 31%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Financial Services	12.9
Pharmaceuticals, Biotechnology & Life Sciences	12.1
Banks	11.1
Media & Entertainment	10.4
Health Care Equipment & Services	8.1
Energy	8.0
Technology Hardware & Equipment	5.2
Food, Beverage & Tobacco	4.1
Software & Services	3.7
Consumer Discretionary Distribution & Retail	3.3
Consumer Durables & Apparel	3.1
Capital Goods	3.1
Materials	2.7
Automobiles & Components	2.6
Telecommunication Services	2.4
Semiconductors & Semiconductor Equipment	1.9
Insurance	1.8
Consumer Staples Distribution & Retail	1.5
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000241011

Shareholder Report [Line Items]

Fund Name

GMO U.S. Opportunistic Value Fund

Class Name

Class VI

Trading Symbol

UUOAX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$21	0.39%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 21

Expense Ratio, Percent

0.39%

AssetsNet

$ 556,244,271

Holdings Count | Holding

149

InvestmentCompanyPortfolioTurnover

29.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$556,244,271
# of Portfolio Holdings	149
Portfolio Turnover Rate	29%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 31%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Financial Services	12.9
Pharmaceuticals, Biotechnology & Life Sciences	12.1
Banks	11.1
Media & Entertainment	10.4
Health Care Equipment & Services	8.1
Energy	8.0
Technology Hardware & Equipment	5.2
Food, Beverage & Tobacco	4.1
Software & Services	3.7
Consumer Discretionary Distribution & Retail	3.3
Consumer Durables & Apparel	3.1
Capital Goods	3.1
Materials	2.7
Automobiles & Components	2.6
Telecommunication Services	2.4
Semiconductors & Semiconductor Equipment	1.9
Insurance	1.8
Consumer Staples Distribution & Retail	1.5
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000241009

Shareholder Report [Line Items]

Fund Name

GMO U.S. Opportunistic Value Fund

Class Name

Class R6

Trading Symbol

PPAJX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$26	0.49%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 26

Expense Ratio, Percent

0.49%

AssetsNet

$ 556,244,271

Holdings Count | Holding

149

InvestmentCompanyPortfolioTurnover

29.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$556,244,271
# of Portfolio Holdings	149
Portfolio Turnover Rate	29%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 31%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Financial Services	12.9
Pharmaceuticals, Biotechnology & Life Sciences	12.1
Banks	11.1
Media & Entertainment	10.4
Health Care Equipment & Services	8.1
Energy	8.0
Technology Hardware & Equipment	5.2
Food, Beverage & Tobacco	4.1
Software & Services	3.7
Consumer Discretionary Distribution & Retail	3.3
Consumer Durables & Apparel	3.1
Capital Goods	3.1
Materials	2.7
Automobiles & Components	2.6
Telecommunication Services	2.4
Semiconductors & Semiconductor Equipment	1.9
Insurance	1.8
Consumer Staples Distribution & Retail	1.5
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000241012

Shareholder Report [Line Items]

Fund Name

GMO U.S. Opportunistic Value Fund

Class Name

Class I

Trading Symbol

PPAEX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Opportunistic Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$31	0.59%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 31

Expense Ratio, Percent

0.59%

AssetsNet

$ 556,244,271

Holdings Count | Holding

149

InvestmentCompanyPortfolioTurnover

29.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$556,244,271
# of Portfolio Holdings	149
Portfolio Turnover Rate	29%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 31%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Financial Services	12.9
Pharmaceuticals, Biotechnology & Life Sciences	12.1
Banks	11.1
Media & Entertainment	10.4
Health Care Equipment & Services	8.1
Energy	8.0
Technology Hardware & Equipment	5.2
Food, Beverage & Tobacco	4.1
Software & Services	3.7
Consumer Discretionary Distribution & Retail	3.3
Consumer Durables & Apparel	3.1
Capital Goods	3.1
Materials	2.7
Automobiles & Components	2.6
Telecommunication Services	2.4
Semiconductors & Semiconductor Equipment	1.9
Insurance	1.8
Consumer Staples Distribution & Retail	1.5
Other (each less than 1%)	2.0

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000212810

Shareholder Report [Line Items]

Fund Name

GMO U.S. Small Cap Value Fund

Class Name

Class VI

Trading Symbol

GCAVX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Small Cap Value Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$25	0.47%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 25

Expense Ratio, Percent

0.47%

AssetsNet

$ 40,979,666

Holdings Count | Holding

264

InvestmentCompanyPortfolioTurnover

44.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$40,979,666
# of Portfolio Holdings	264
Portfolio Turnover Rate	44%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 45%.

Holdings [Text Block]

Industry Group Summary^{Footnote Reference*}

% of Investments

Financial Services	14.1
Banks	11.3
Capital Goods	10.8
Commercial & Professional Services	8.4
Consumer Durables & Apparel	7.4
Insurance	6.9
Semiconductors & Semiconductor Equipment	5.3
Equity Real Estate Investment Trusts (REITS)	5.0
Consumer Discretionary Distribution & Retail	5.0
Technology Hardware & Equipment	4.1
Materials	3.7
Energy	3.1
Consumer Services	3.1
Pharmaceuticals, Biotechnology & Life Sciences	2.8
Health Care Equipment & Services	1.6
Food, Beverage & Tobacco	1.6
Transportation	1.1
Automobiles & Components	1.1
Other (each less than 1%)	3.6

Footnote	Description
Footnote^*	Excludes short-term investments, mutual funds and derivative financial instruments, if any.

C000075103

Shareholder Report [Line Items]

Fund Name

GMO Asset Allocation Bond Fund

Class Name

Class VI

Trading Symbol

GABFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Asset Allocation Bond Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$18	0.34%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 18

Expense Ratio, Percent

0.34%

AssetsNet

$ 43,540,113

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

98.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$43,540,113
# of Portfolio Holdings	12
Portfolio Turnover Rate	98%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Short-Term Investments	86.5
Debt Obligations	15.9
Swap Contracts	0.8
Forward Currency Contracts	(0.3)
Futures Contracts	(1.9)
Other	(1.0)

C000013327

Shareholder Report [Line Items]

Fund Name

GMO Emerging Country Debt Fund

Class Name

Class III

Trading Symbol

GMCDX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Country Debt Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$30	0.57%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 30

Expense Ratio, Percent

0.57%

AssetsNet

$ 2,226,247,348

Holdings Count | Holding

327

InvestmentCompanyPortfolioTurnover

12.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,226,247,348
# of Portfolio Holdings	327
Portfolio Turnover Rate	12%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	93.3
Short-Term Investments	2.0
Loan Assignments	1.4
Rights/Warrants	1.0
Investment Funds	0.6
Loan Participations	0.3
Forward Currency Contracts	0.0
Swap Contracts	0.0
Reverse Repurchase Agreements	(1.0)
Other	2.4

C000013328

Shareholder Report [Line Items]

Fund Name

GMO Emerging Country Debt Fund

Class Name

Class IV

Trading Symbol

GMDFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Country Debt Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$27	0.52%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 27

Expense Ratio, Percent

0.52%

AssetsNet

$ 2,226,247,348

Holdings Count | Holding

327

InvestmentCompanyPortfolioTurnover

12.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,226,247,348
# of Portfolio Holdings	327
Portfolio Turnover Rate	12%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	93.3
Short-Term Investments	2.0
Loan Assignments	1.4
Rights/Warrants	1.0
Investment Funds	0.6
Loan Participations	0.3
Forward Currency Contracts	0.0
Swap Contracts	0.0
Reverse Repurchase Agreements	(1.0)
Other	2.4

C000013330

Shareholder Report [Line Items]

Fund Name

GMO Emerging Country Debt Fund

Class Name

Class VI

Trading Symbol

GMOQX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Emerging Country Debt Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$25	0.48%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 25

Expense Ratio, Percent

0.48%

AssetsNet

$ 2,226,247,348

Holdings Count | Holding

327

InvestmentCompanyPortfolioTurnover

12.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,226,247,348
# of Portfolio Holdings	327
Portfolio Turnover Rate	12%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	93.3
Short-Term Investments	2.0
Loan Assignments	1.4
Rights/Warrants	1.0
Investment Funds	0.6
Loan Participations	0.3
Forward Currency Contracts	0.0
Swap Contracts	0.0
Reverse Repurchase Agreements	(1.0)
Other	2.4

C000199930

Shareholder Report [Line Items]

Fund Name

GMO High Yield Fund

Class Name

Class VI

Trading Symbol

GHVIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO High Yield Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$24	0.46%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 24

Expense Ratio, Percent

0.46%

AssetsNet

$ 148,647,932

Holdings Count | Holding

112

InvestmentCompanyPortfolioTurnover

88.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$148,647,932
# of Portfolio Holdings	112
Portfolio Turnover Rate	88%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	55.0
Short-Term Investments	44.5
Swap Contracts	3.5
Futures Contracts	(0.0)
Forward Currency Contracts	(1.7)
Other	(1.3)

C000213400

Shareholder Report [Line Items]

Fund Name

GMO High Yield Fund

Class Name

Class I

Trading Symbol

GMOZX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO High Yield Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$32	0.62%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 32

Expense Ratio, Percent

0.62%

AssetsNet

$ 148,647,932

Holdings Count | Holding

112

InvestmentCompanyPortfolioTurnover

88.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$148,647,932
# of Portfolio Holdings	112
Portfolio Turnover Rate	88%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	55.0
Short-Term Investments	44.5
Swap Contracts	3.5
Futures Contracts	(0.0)
Forward Currency Contracts	(1.7)
Other	(1.3)

C000013294

Shareholder Report [Line Items]

Fund Name

GMO Multi-Sector Fixed Income Fund

Class Name

Class III

Trading Symbol

GUGAX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Multi-Sector Fixed Income Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$17	0.33%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 17

Expense Ratio, Percent

0.33%

AssetsNet

$ 81,516,872

Holdings Count | Holding

362

InvestmentCompanyPortfolioTurnover

209.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$81,516,872
# of Portfolio Holdings	362
Portfolio Turnover Rate	209%

Holdings [Text Block]

Asset Class Summary^{Footnote Reference*}

% of Total Net Assets

Debt Obligations	63.6
Short-Term Investments	44.1
Common Stocks	14.2
Swap Contracts	0.1
Loan Assignments	0.1
Rights/Warrants	0.1
Investment Funds	0.0
Loan Participations	0.0
Purchased Options	0.0
Written Options	(0.0)
Reverse Repurchase Agreements	(0.0)
Futures Contracts	(0.3)
Securities Sold Short	(0.8)
Forward Currency Contracts	(1.1)
Other	(20.0)

Footnote	Description
Footnote^*	Includes exposures associated with investments in other funds of GMO Trust.

C000013295

Shareholder Report [Line Items]

Fund Name

GMO Multi-Sector Fixed Income Fund

Class Name

Class IV

Trading Symbol

GPBFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Multi-Sector Fixed Income Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$14	0.28%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 14

Expense Ratio, Percent

0.28%

AssetsNet

$ 81,516,872

Holdings Count | Holding

362

InvestmentCompanyPortfolioTurnover

209.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$81,516,872
# of Portfolio Holdings	362
Portfolio Turnover Rate	209%

Holdings [Text Block]

Asset Class Summary^{Footnote Reference*}

% of Total Net Assets

Debt Obligations	63.6
Short-Term Investments	44.1
Common Stocks	14.2
Swap Contracts	0.1
Loan Assignments	0.1
Rights/Warrants	0.1
Investment Funds	0.0
Loan Participations	0.0
Purchased Options	0.0
Written Options	(0.0)
Reverse Repurchase Agreements	(0.0)
Futures Contracts	(0.3)
Securities Sold Short	(0.8)
Forward Currency Contracts	(1.1)
Other	(20.0)

Footnote	Description
Footnote^*	Includes exposures associated with investments in other funds of GMO Trust.

C000137450

Shareholder Report [Line Items]

Fund Name

GMO Opportunistic Income Fund

Class Name

Class III

Trading Symbol

GMOHX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Opportunistic Income Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$30	0.58%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 30

Expense Ratio, Percent

0.58%

AssetsNet

$ 1,588,520,786

Holdings Count | Holding

332

InvestmentCompanyPortfolioTurnover

110.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,588,520,786
# of Portfolio Holdings	332
Portfolio Turnover Rate	110%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 109%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	83.3
Short-Term Investments	22.9
Mutual Funds	0.7
Swap Contracts	0.4
Purchased Options	0.0
Written Options	(0.0)
Futures Contracts	(0.0)
Securities Sold Short	(4.6)
Other	(2.7)

C000020548

Shareholder Report [Line Items]

Fund Name

GMO Opportunistic Income Fund

Class Name

Class VI

Trading Symbol

GMODX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Opportunistic Income Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$25	0.48%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 25

Expense Ratio, Percent

0.48%

AssetsNet

$ 1,588,520,786

Holdings Count | Holding

332

InvestmentCompanyPortfolioTurnover

110.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,588,520,786
# of Portfolio Holdings	332
Portfolio Turnover Rate	110%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 109%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	83.3
Short-Term Investments	22.9
Mutual Funds	0.7
Swap Contracts	0.4
Purchased Options	0.0
Written Options	(0.0)
Futures Contracts	(0.0)
Securities Sold Short	(4.6)
Other	(2.7)

C000213385

Shareholder Report [Line Items]

Fund Name

GMO Opportunistic Income Fund

Class Name

Class R6

Trading Symbol

GAAAX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Opportunistic Income Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$30	0.58%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 30

Expense Ratio, Percent

0.58%

AssetsNet

$ 1,588,520,786

Holdings Count | Holding

332

InvestmentCompanyPortfolioTurnover

110.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,588,520,786
# of Portfolio Holdings	332
Portfolio Turnover Rate	110%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 109%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	83.3
Short-Term Investments	22.9
Mutual Funds	0.7
Swap Contracts	0.4
Purchased Options	0.0
Written Options	(0.0)
Futures Contracts	(0.0)
Securities Sold Short	(4.6)
Other	(2.7)

C000213384

Shareholder Report [Line Items]

Fund Name

GMO Opportunistic Income Fund

Class Name

Class I

Trading Symbol

GMOLX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Opportunistic Income Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$35	0.68%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 35

Expense Ratio, Percent

0.68%

AssetsNet

$ 1,588,520,786

Holdings Count | Holding

332

InvestmentCompanyPortfolioTurnover

110.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,588,520,786
# of Portfolio Holdings	332
Portfolio Turnover Rate	110%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 109%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Debt Obligations	83.3
Short-Term Investments	22.9
Mutual Funds	0.7
Swap Contracts	0.4
Purchased Options	0.0
Written Options	(0.0)
Futures Contracts	(0.0)
Securities Sold Short	(4.6)
Other	(2.7)

C000075084

Shareholder Report [Line Items]

Fund Name

GMO U.S. Treasury Fund

Class Name

Class VI

Trading Symbol

GUSTX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO U.S. Treasury Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$5	0.09%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 5

Expense Ratio, Percent

0.09%

AssetsNet

$ 425,294,464

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

0.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$425,294,464
# of Portfolio Holdings	12
Portfolio Turnover Rate	0%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Short-Term Investments

100.0

C000211299

Shareholder Report [Line Items]

Fund Name

GMO Alternative Allocation Fund

Class Name

Class VI

Trading Symbol

GAAVX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Alternative Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

<span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 400; grid-area: auto; line-height: 16px; margin: 0px; overflow: visible; text-align: left;">https://www.gmo.com/americas/mutual-fund-documents/</span>

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class VI	$96^{Footnote Reference1}	1.89%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses may be material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 96

Expense Ratio, Percent

1.89%

AssetsNet

$ 185,475,734

Holdings Count | Holding

922

InvestmentCompanyPortfolioTurnover

489.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$185,475,734
# of Portfolio Holdings	922
Portfolio Turnover Rate	489%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Common Stocks	101.2
Debt Obligations	62.5
Short-Term Investments	15.9
GMO International Equity Funds	1.8
Investment Funds	1.1
Preferred Stocks	0.6
Rights/Warrants	0.3
Purchased Options	0.0
Written Options	(0.2)
Futures Contracts	(1.1)
Forward Currency Contracts	(1.2)
Swap Contracts	(2.0)
Securities Sold Short	(65.1)
Other	(13.8)

C000213405

Shareholder Report [Line Items]

Fund Name

GMO Alternative Allocation Fund

Class Name

Class R6

Trading Symbol

GAAKX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Alternative Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$106^{Footnote Reference1}	2.09%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses may be material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 106

Expense Ratio, Percent

2.09%

AssetsNet

$ 185,475,734

Holdings Count | Holding

922

InvestmentCompanyPortfolioTurnover

489.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$185,475,734
# of Portfolio Holdings	922
Portfolio Turnover Rate	489%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Common Stocks	101.2
Debt Obligations	62.5
Short-Term Investments	15.9
GMO International Equity Funds	1.8
Investment Funds	1.1
Preferred Stocks	0.6
Rights/Warrants	0.3
Purchased Options	0.0
Written Options	(0.2)
Futures Contracts	(1.1)
Forward Currency Contracts	(1.2)
Swap Contracts	(2.0)
Securities Sold Short	(65.1)
Other	(13.8)

C000213406

Shareholder Report [Line Items]

Fund Name

GMO Alternative Allocation Fund

Class Name

Class I

Trading Symbol

GAAGX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Alternative Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$110^{Footnote Reference1}	2.17%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses may be material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 110

Expense Ratio, Percent

2.17%

AssetsNet

$ 185,475,734

Holdings Count | Holding

922

InvestmentCompanyPortfolioTurnover

489.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$185,475,734
# of Portfolio Holdings	922
Portfolio Turnover Rate	489%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Common Stocks	101.2
Debt Obligations	62.5
Short-Term Investments	15.9
GMO International Equity Funds	1.8
Investment Funds	1.1
Preferred Stocks	0.6
Rights/Warrants	0.3
Purchased Options	0.0
Written Options	(0.2)
Futures Contracts	(1.1)
Forward Currency Contracts	(1.2)
Swap Contracts	(2.0)
Securities Sold Short	(65.1)
Other	(13.8)

C000014927

Shareholder Report [Line Items]

Fund Name

GMO Benchmark-Free Allocation Fund

Class Name

Class III

Trading Symbol

GBMFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Benchmark-Free Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$40^{Footnote Reference1}	0.77%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 40

Expense Ratio, Percent

0.77%

AssetsNet

$ 2,543,168,072

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,543,168,072
# of Portfolio Holdings	6
Portfolio Turnover Rate	6%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO Implementation Funds^{Footnote Reference*}	92.1
GMO Fixed Income Funds	6.9
GMO International Equity Funds	1.0
Short-Term Investments	0.1
Other	(0.1)

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000109350

Shareholder Report [Line Items]

Fund Name

GMO Benchmark-Free Allocation Fund

Class Name

Class IV

Trading Symbol

GBMBX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Benchmark-Free Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class IV	$37^{Footnote Reference1}	0.72%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 37

Expense Ratio, Percent

0.72%

AssetsNet

$ 2,543,168,072

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,543,168,072
# of Portfolio Holdings	6
Portfolio Turnover Rate	6%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO Implementation Funds^{Footnote Reference*}	92.1
GMO Fixed Income Funds	6.9
GMO International Equity Funds	1.0
Short-Term Investments	0.1
Other	(0.1)

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000213373

Shareholder Report [Line Items]

Fund Name

GMO Benchmark-Free Allocation Fund

Class Name

Class R6

Trading Symbol

GBMSX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Benchmark-Free Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$40^{Footnote Reference1}	0.77%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 40

Expense Ratio, Percent

0.77%

AssetsNet

$ 2,543,168,072

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,543,168,072
# of Portfolio Holdings	6
Portfolio Turnover Rate	6%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO Implementation Funds^{Footnote Reference*}	92.1
GMO Fixed Income Funds	6.9
GMO International Equity Funds	1.0
Short-Term Investments	0.1
Other	(0.1)

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000213372

Shareholder Report [Line Items]

Fund Name

GMO Benchmark-Free Allocation Fund

Class Name

Class I

Trading Symbol

GBMIX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Benchmark-Free Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$46^{Footnote Reference1}	0.88%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 46

Expense Ratio, Percent

0.88%

AssetsNet

$ 2,543,168,072

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,543,168,072
# of Portfolio Holdings	6
Portfolio Turnover Rate	6%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO Implementation Funds^{Footnote Reference*}	92.1
GMO Fixed Income Funds	6.9
GMO International Equity Funds	1.0
Short-Term Investments	0.1
Other	(0.1)

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000102896

Shareholder Report [Line Items]

Fund Name

GMO Benchmark-Free Fund

Class Name

Class III

Trading Symbol

GBFFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Benchmark-Free Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$24^{Footnote Reference1}	0.45%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses may be material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 24

Expense Ratio, Percent

0.45%

AssetsNet

$ 1,066,812,239

Holdings Count | Holding

1,444

InvestmentCompanyPortfolioTurnover

54.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$1,066,812,239
# of Portfolio Holdings	1,444
Portfolio Turnover Rate	54%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 64%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Common Stocks	78.7
Debt Obligations	19.4
GMO Fixed Income Funds	8.6
Short-Term Investments	6.8
GMO International Equity Funds	5.7
Preferred Stocks	1.3
GMO Implementation Funds^{Footnote Reference*}	0.0
Futures Contracts	(0.0)
Swap Contracts	(0.0)
Securities Sold Short	(19.4)
Other	(1.1)

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000014933

Shareholder Report [Line Items]

Fund Name

GMO Global Asset Allocation Fund

Class Name

Class III

Trading Symbol

GMWAX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Global Asset Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 381,818,378

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$381,818,378
# of Portfolio Holdings	20
Portfolio Turnover Rate	6%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 6%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	43.3
GMO U.S. Equity Funds	20.3
GMO Fixed Income Funds	17.7
GMO Alternative Funds	12.2
GMO Implementation Funds^{Footnote Reference*}	6.4
Short-Term Investments	0.0
Other	0.1

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000213376

Shareholder Report [Line Items]

Fund Name

GMO Global Asset Allocation Fund

Class Name

Class R6

Trading Symbol

GMWRX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Global Asset Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 381,818,378

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$381,818,378
# of Portfolio Holdings	20
Portfolio Turnover Rate	6%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 6%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	43.3
GMO U.S. Equity Funds	20.3
GMO Fixed Income Funds	17.7
GMO Alternative Funds	12.2
GMO Implementation Funds^{Footnote Reference*}	6.4
Short-Term Investments	0.0
Other	0.1

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000213377

Shareholder Report [Line Items]

Fund Name

GMO Global Asset Allocation Fund

Class Name

Class I

Trading Symbol

GMOOX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Global Asset Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$6^{Footnote Reference1}	0.12%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 6

Expense Ratio, Percent

0.12%

AssetsNet

$ 381,818,378

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

6.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$381,818,378
# of Portfolio Holdings	20
Portfolio Turnover Rate	6%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 6%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	43.3
GMO U.S. Equity Funds	20.3
GMO Fixed Income Funds	17.7
GMO Alternative Funds	12.2
GMO Implementation Funds^{Footnote Reference*}	6.4
Short-Term Investments	0.0
Other	0.1

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

C000014938

Shareholder Report [Line Items]

Fund Name

GMO Global Developed Equity Allocation Fund

Class Name

Class III

Trading Symbol

GWOAX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Global Developed Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 77,917,320

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

5.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$77,917,320
# of Portfolio Holdings	13
Portfolio Turnover Rate	5%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	53.9
GMO U.S. Equity Funds	46.0
Short-Term Investments	0.1

C000014936

Shareholder Report [Line Items]

Fund Name

GMO Global Equity Allocation Fund

Class Name

Class III

Trading Symbol

GMGEX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Global Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 683,039,920

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

11.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$683,039,920
# of Portfolio Holdings	14
Portfolio Turnover Rate	11%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	61.3
GMO U.S. Equity Funds	38.6
Short-Term Investments	0.1

C000213379

Shareholder Report [Line Items]

Fund Name

GMO Global Equity Allocation Fund

Class Name

Class R6

Trading Symbol

GMADX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Global Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 683,039,920

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

11.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$683,039,920
# of Portfolio Holdings	14
Portfolio Turnover Rate	11%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	61.3
GMO U.S. Equity Funds	38.6
Short-Term Investments	0.1

C000213378

Shareholder Report [Line Items]

Fund Name

GMO Global Equity Allocation Fund

Class Name

Class I

Trading Symbol

GAAUX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Global Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class I	$6^{Footnote Reference1}	0.12%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 6

Expense Ratio, Percent

0.12%

AssetsNet

$ 683,039,920

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

11.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$683,039,920
# of Portfolio Holdings	14
Portfolio Turnover Rate	11%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	61.3
GMO U.S. Equity Funds	38.6
Short-Term Investments	0.1

C000110451

Shareholder Report [Line Items]

Fund Name

GMO Implementation Fund

Class Name

Core Class

Trading Symbol

GIMFX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Implementation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Core Class	$21	0.41%^{Footnote Reference1}

Footnote	Description
Footnote¹	Annualized.

Expenses Paid, Amount

$ 21

Expense Ratio, Percent

0.41%

AssetsNet

$ 2,440,843,542

Holdings Count | Holding

1,681

InvestmentCompanyPortfolioTurnover

74.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$2,440,843,542
# of Portfolio Holdings	1,681
Portfolio Turnover Rate	74%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 76%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

Common Stocks	85.6
Debt Obligations	31.9
Short-Term Investments	1.7
Preferred Stocks	1.6
Investment Funds	0.3
Rights/Warrants	0.0
GMO Implementation Funds^{Footnote Reference*}	0.0
Written Options	(0.0)
Swap Contracts	(0.0)
Futures Contracts	(0.2)
Forward Currency Contracts	(0.2)
Securities Sold Short	(22.5)
Other	1.8

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.

Largest Holdings [Text Block]

Top Ten Holdings

% of Investments

U.S. Treasury Floating Rate Notes , 5.19%, due 04/30/26	7.9
U.S. Treasury Floating Rate Notes , 5.23%, due 07/31/26	6.0
U.S. Treasury Inflation-Indexed Notes , 1.88%, due 07/15/34	3.7
U.S. Treasury Inflation-Indexed Notes , 1.75%, due 01/15/34	3.7
U.S. Treasury Floating Rate Notes , 5.21%, due 04/30/25	2.1
U.S. Treasury Floating Rate Notes , 5.29%, due 01/31/26	2.0
Federal Home Loan Banks , 5.43%, due 09/04/24	1.4
Taiwan Semiconductor Manufacturing Co. Ltd.	0.7
Roche Holding AG	0.7
Meta Platforms, Inc., Class A	0.5

Material Fund Change [Text Block]

C000033342

Shareholder Report [Line Items]

Fund Name

GMO International Developed Equity Allocation Fund

Class Name

Class III

Trading Symbol

GIOTX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Developed Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 300,401,106

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

8.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$300,401,106
# of Portfolio Holdings	4
Portfolio Turnover Rate	8%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	99.9
Short-Term Investments	0.1

C000213387

Shareholder Report [Line Items]

Fund Name

GMO International Developed Equity Allocation Fund

Class Name

Class R6

Trading Symbol

GAAWX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Developed Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 300,401,106

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

8.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$300,401,106
# of Portfolio Holdings	4
Portfolio Turnover Rate	8%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	99.9
Short-Term Investments	0.1

C000014930

Shareholder Report [Line Items]

Fund Name

GMO International Equity Allocation Fund

Class Name

Class III

Trading Symbol

GIEAX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 315,299,157

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

11.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$315,299,157
# of Portfolio Holdings	5
Portfolio Turnover Rate	11%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	99.9
Short-Term Investments	0.1

C000213374

Shareholder Report [Line Items]

Fund Name

GMO International Equity Allocation Fund

Class Name

Class R6

Trading Symbol

GSXMX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO International Equity Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class R6	$1^{Footnote Reference1}	0.01%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 1

Expense Ratio, Percent

0.01%

AssetsNet

$ 315,299,157

Holdings Count | Holding

InvestmentCompanyPortfolioTurnover

11.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$315,299,157
# of Portfolio Holdings	5
Portfolio Turnover Rate	11%

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	99.9
Short-Term Investments	0.1

C000014937

Shareholder Report [Line Items]

Fund Name

GMO Strategic Opportunities Allocation Fund

Class Name

Class III

Trading Symbol

GBATX

Annual or Semi-Annual Statement [Text Block]

This semi-annual shareholder report contains important information about GMO Strategic Opportunities Allocation Fund for the period of March 1, 2024 to August 31, 2024.

Shareholder Report Annual or Semi-Annual

Semi-Annual Shareholder Report

Additional Information [Text Block]

You can find additional information about the Fund at https://www.gmo.com/americas/mutual-fund-documents/. You can also request this information by contacting us at (617) 346-7646 (collect).

Additional Information Phone Number

(617) 346-7646

Additional Information Website

Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment)

Class Name	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Class III	$20^{Footnote Reference1}	0.39%^{Footnote Reference1 ,}^{Footnote Reference2}

Footnote	Description
Footnote¹	The costs do not reflect fees and expenses of underlying funds. Those fees and expenses are material and, if reflected, the costs in the table would be higher. Please refer to the prospectus for more information about the fees and expenses of an investment in the Fund, including fees and expenses of underlying funds in which the Fund invests.
Footnote²	Annualized.

Expenses Paid, Amount

$ 20

Expense Ratio, Percent

0.39%

AssetsNet

$ 203,148,613

Holdings Count | Holding

440

InvestmentCompanyPortfolioTurnover

25.00%

Additional Fund Statistics [Text Block]

Key Fund Statistics

Total Net Assets	$203,148,613
# of Portfolio Holdings	440
Portfolio Turnover Rate	25%^{Footnote Reference*}

Footnote	Description
Footnote^*	The portfolio turnover rate excludes investments in GMO U.S. Treasury Fund ("USTF") which is used as a short-term investment vehicle for cash management. The portfolio turnover rate including transactions in USTF during the period was 25%.

Holdings [Text Block]

Asset Class Summary

% of Total Net Assets

GMO International Equity Funds	45.5
Common Stocks	22.0
GMO U.S. Equity Funds	20.7
Short-Term Investments	12.6
GMO Implementation Funds^{Footnote Reference*}	7.9
GMO Fixed Income Funds	7.5
Debt Obligations	0.7
Preferred Stocks	0.3
Swap Contracts	(0.0)
Securities Sold Short	(17.2)

Footnote	Description
Footnote^*	Represents a fund utilized by GMO asset allocation funds and accounts and is not intended to serve as a standalone investment.