485BPOS

As filed with the Securities and Exchange Commission on March 20, 2013

1933 Act Registration No. 333-84639

1940 Act Registration No. 811-09521

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933	x
Pre-Effective Amendment No.	¨
Post-Effective Amendment No. 101	x

REGISTRATION STATEMENT

UNDER

THE INVESTMENT COMPANY ACT OF 1940	x
Amendment No. 104	x

MANAGERS AMG FUNDS

(Exact name of registrant as specified in charter)

800 Connecticut Avenue

Norwalk, Connecticut 06854

(Address of principal executive offices)

Registrant’s telephone number, including area code: (800) 835-3879

Gregory C. Davis

Rajib Chanda

Ropes & Gray LLP

Three Embarcadero Center

San Francisco, CA 94111-4006

(Name and address of agent for service)

It is proposed that this filing will become effective:

x immediately upon filing pursuant to paragraph (b)

¨ on (date) pursuant to paragraph (b)

¨ 60 days after filing pursuant to paragraph (a)(1)

¨ on (date) pursuant to paragraph (a)(1)

¨ 75 days after filing pursuant to paragraph (a)(2)

¨ On (date) pursuant to (a)(2) of rule 485

If appropriate, check the following box:

¨ This post-effective amendment designates a new effective date for a previously filed post-effective amendment.

The Amendment relates solely to Trilogy Global Equity Fund, Trilogy Emerging Markets Equity Fund and Trilogy International Small Cap Fund, each a series of Managers AMG Funds.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, each as amended, Managers AMG Funds certifies that it meets all of the requirements for effectiveness of this registration statement under Rule 485(b) under the Securities Act of 1933, as amended, and has duly caused this amendment to the registration statement to be signed on its behalf by the undersigned, duly authorized, in the City of Norwalk, and State of Connecticut, on the 20th day of March, 2013.

MANAGERS AMG FUNDS
By:	/s/ Donald S. Rumery
	Donald S. Rumery
	Treasurer, Chief Financial Officer, and
	Principal Financial Officer

Pursuant to the requirements of the Securities Act, this amendment to the registration statement has been signed below by the following persons in the capacities and on the date indicated:

Signature	Title	Date
/s/ Bruce B. Bingham*	Trustee	March 20, 2013
Bruce B. Bingham
/s/ Christine C. Carsman*	Trustee	March 20, 2013
Christine C. Carsman
/s/ William E. Chapman, II*	Trustee	March 20, 2013
William E. Chapman, II
/s/ Edward J. Kaier*	Trustee	March 20, 2013
Edward J. Kaier
/s/ Steven J. Paggioli*	Trustee	March 20, 2013
Steven J. Paggioli
/s/ Eric Rakowski*	Trustee	March 20, 2013
Eric Rakowski
/s/ Thomas R. Schneeweis*	Trustee	March 20, 2013
Thomas R. Schneeweis
/s/ Keitha L. Kinne	President and	March 20, 2013
Keitha L. Kinne	Principal Executive Officer
	(Principal Executive Officer)
/s/ Donald S. Rumery	Treasurer,	March 20, 2013
Donald S. Rumery	Chief Financial Officer, and
	Principal Financial Officer
	(Principal Accounting Officer)
	(Principal Financial Officer)

*By:	/s/ Donald S. Rumery
	Donald S. Rumery
	Pursuant to Powers of Attorney incorporated herein by reference
	Date: March 20, 2013

Managers AMG Funds

Exhibit Index

Exhibit No.	Description
EX-101.INS	XBRL Instance Document
EX-101.SCH	XBRL Taxonomy Extension Schema Document
EX-101.CAL	XBRL Taxonomy Extension Calculation Linkbase
EX.101.DEF	XBRL Taxonomy Extension Definition Linkbase
EX.101.LAB	XBRL Taxonomy Extension Labels Linkbase
EX-101.PRE	XBRL Taxonomy Extension Presentation Linkbase

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Trilogy Emerging Markets Equity Fund

Trilogy Emerging Markets Equity Fund

INVESTMENT OBJECTIVE

The Trilogy Emerging Markets Equity Fund's (the "Fund" or "Emerging Markets Equity Fund") investment objective is to seek long-term capital appreciation.

FEES AND EXPENSES OF THE FUND

The tables below describe the fees and expenses that you may pay if you buy and hold shares of the Fund.

Shareholder Fees
(fees paid directly from your investment)

Shareholder Fees Trilogy Emerging Markets Equity Fund	Investor Class	Service Class	Institutional Class
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	2.00%	2.00%	2.00%

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses Trilogy Emerging Markets Equity Fund		Investor Class	Service Class	Institutional Class
Management Fee		0.70%	0.70%	0.70%
Distribution and Service (12b-1) Fees		0.25%	none	none
Other Expenses		0.35%	0.55%	0.35%
Acquired Fund Fees and Expenses		0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	[1]	1.31%	1.26%	none
Fee Waiver and Expense Reimbursements	[2]	none	none	none
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	[1]	1.31%	1.26%	1.06%

EXPENSE EXAMPLE

This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund's operating expenses remain the same. The Example reflects the impact of the Fund's contractual expense limitation through March 1, 2014. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:

Expense Example Trilogy Emerging Markets Equity Fund (USD $)	1 Year	3 Years	5 Years	10 Years
Investor Class	133	415	718	1,579
Service Class	128	400	692	1,523
Institutional Class	108	337	585	1,294

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 32% of the average value of its portfolio.

PRINCIPAL INVESTMENT STRATEGIES

Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities (generally common and preferred stocks) of issuers located in emerging market countries. The Fund may allocate investments across different emerging markets countries. The Subadvisor considers emerging market countries to be any country other than Canada, Luxembourg, the United States and the countries comprising the MSCI EAFE Index. The Fund considers an issuer to be located in an emerging market country if the issuer maintains its principal place of business in an emerging market country, its securities are traded principally in an emerging market country, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed in an emerging market country or it has at least 50% of its assets in an emerging market country. The Fund's portfolio normally consists of between 60 to 120 securities. To gain exposure to foreign issuers, the Fund also may invest in American Depositary Receipts ("ADRs"), Global Depositary Receipts ("GDRs") and other depositary receipts of non-U.S. listed companies.

The Subadvisor uses a bottom-up investment process driven by fundamental research conducted by its investment analysts. Under normal market conditions, the Subadvisor seeks to maintain a growth oriented focus and invest the Fund's assets pursuant to the following core principles:

—  Earnings growth drives equity returns over the long term.

—  Early-stage and traditional growth companies provide the greatest opportunity.

—  Risk management with respect to the Fund's portfolio should focus on avoiding losing money, rather than minimizing tracking error against the benchmark.

—  A disciplined investment process requires consistently identifying opportunities, evaluating potential returns and responding with timely buy/sell decisions.

PRINCIPAL RISKS

There is the risk that you may lose money on your investment. All investments carry a certain amount of risk and the Fund cannot guarantee that it will achieve its investment objective. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. Below are some of the risks of investing in the Fund.

Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars.

Derivatives Risk—the complexity and rapidly changing structure of derivatives markets may increase the possibility of market losses.

Emerging Markets Risk—investments in emerging markets can be subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility.

Foreign Securities Risk—securities or other investments of foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investing in securities of U.S. issuers and may result in greater price volatility.

Growth Stock Risk—growth stocks may be more sensitive to market movements because their prices tend to reflect future investor expectations rather than just current profits.

Large-Capitalization Stock Risk—the stocks of large-capitalization companies are generally more mature and may not be able to reach the same levels of growth as the stocks of small- or mid-capitalization companies.

Liquidity Risk—particular investments, such as illiquid securities, may not be able to be sold at the price the Fund would like or the Fund may have to sell them at a loss.

Market Risk—market prices of securities held by the Fund may fall rapidly or unpredictably due to a variety of factors, including changing economic, political, or market conditions. Equity investments generally have greater volatility than fixed income investments.

Political Risk—changes in the political status of any country can have profound effects on the value of investments exposed to that country.

Small- and Mid-Capitalization Stock Risk—the stocks of small- and mid-capitalization companies often have greater price volatility, lower trading volume, and less liquidity than the stocks of larger, more established companies.

PERFORMANCE

The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. Because the Fund's Investor Class shares have not operated for a full calendar year, performance history for this share class is not available. Investor Class shares would have similar annual returns as Service Class and Institutional Class shares because all of the classes are invested in the same portfolio of securities. However, Investor Class shares are subject to different expenses than Service Class and Institutional Class shares, and Investor Class share performance would vary to that extent. To obtain updated performance information please visit www.managersinvest.com or call 800.835.3879.

Calendar Year Total Returns as of (12/31/12) Institutional Class

Best Quarter: 4.70 (4^th Quarter 2012)
Worst Quarter: 24.01 (3^rd Quarter 2011)

Average Annual Total Returns as of 12/31/12

Average Annual Total Returns Trilogy Emerging Markets Equity Fund	1 Year	Since Inception	Inception Date
Service Class	17.37%	1.53%	Mar. 01, 2011
Service Class MSCI Emerging Markets Index (reflects no deduction for fees, expenses, or taxes)	18.22%	0.15%	Mar. 01, 2011
Institutional Class	15.52%	(5.18%)	Mar. 01, 2011
Institutional Class Return After Taxes on Distributions	15.60%	(5.14%)	Mar. 01, 2011
Institutional Class Return After Taxes on Distributions and Sale of Fund Shares	10.42%	(4.29%)	Mar. 01, 2011
Institutional Class MSCI Emerging Markets Index (reflects no deduction for fees, expenses, or taxes)	18.22%	0.15%	Mar. 01, 2011

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Institutional Class shares only, and after-tax returns for Service Class and Investor Class shares will vary.

[1] The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.

[2] Managers Investment Group LLC (the "Investment Manager") has contractually agreed, through at least March 1, 2014, to waive management fees and/or reimburse Fund expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest, shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions, acquired fund fees and expenses, and extraordinary items) to 1.05% of the Fund's average daily net assets, subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months from the time of any waiver, reimbursement, or payment pursuant to the Fund's contractual expense limitation, the Investment Manager may recover from the Fund fees waived and expenses paid to the extent that such repayment would not cause the Fund's Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements to exceed the contractual expense limitation amount. Under such arrangement, if the maximum amount of shareholder servicing fees and distribution and service (12b-1) fees were charged to the classes under the current applicable plans, the total annual fund operating expenses (excluding the other items noted in the parenthetical above) of the Investor Class, Service Class, and Institutional Class would be 1.55%, 1.30% and 1.05% respectively, of the average daily net assets of such classes. The contractual expense limitation may only be terminated upon termination of the Fund's investment advisory agreement with the Investment Manager or by mutual agreement between the Investment Manager and the Fund's Board of Trustees.

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Trilogy Global Equity Fund

Trilogy Global Equity Fund

INVESTMENT OBJECTIVE

The Trilogy Global Equity Fund's (the " Fund") investment objective is to achieve long-term capital appreciation.

FEES AND EXPENSES OF THE FUND

The tables below describes the fees and expenses that you may pay if you buy and hold shares of the Fund.

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses Trilogy Global Equity Fund		Investor Class	Service Class	Institutional Class
Management Fee		0.45%	0.45%	0.45%
Distribution and Service (12b-1) Fees		0.25%	none	none
Other Expenses	[1]	0.36%	0.53%	0.36%
Acquired Fund Fees and Expenses		0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	[2]	1.07%	0.99%	0.82%
Fee Waiver and Expense Reimbursements	[3]	none	none	none
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	[2]	1.07%	0.99%	0.82%

EXPENSE EXAMPLE

This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund's operating expenses remain the same. The Example reflects the impact of the Fund's contractual expense limitation through March 1, 2014. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:

Expense Example Trilogy Global Equity Fund (USD $)	1 Year	3 Years	5 Years	10 Years
Investor Class	109	340	590	1,306
Service Class	101	315	547	1,213
Institutional Class	84	262	455	1,014

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 78% of the average value of its portfolio.

PRINCIPAL INVESTMENT STRATEGIES

Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities (generally common and preferred stocks). Additionally, under normal circumstances, the Fund will invest at least 40% of its net assets, plus the amount of any borrowing for investment purposes, in investments of issuers located outside the United States, and investments exposed to such issuers, and the Fund will invest in or have investments exposed to a minimum of three countries, including the United States. The Fund considers an issuer to be located outside the United States if the issuer maintains its principal place of business outside the United States, its securities are traded principally outside the United States, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed outside the United States or it has at least 50% of its assets outside the United States.

The Fund may allocate investments across all market capitalizations, but investments generally will be in large- and medium- sized companies. Trilogy Global Advisors, L.P, (“Trilogy” or the “Subadvisor”) may invest up to 20% of the Fund’s net assets in securities of issuers located in emerging markets countries. The Subadvisor considers emerging market countries to be any country other than Canada, Luxembourg, the United States and the countries comprising the MSCI EAFE Index. The Fund considers an issuer to be located in an emerging market country if the issuer maintains its principal place of business in an emerging market country, its securities are traded in an emerging market country, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed in an emerging market country or it has at least 50% of its assets in an emerging market country. The Fund’s portfolio normally consists of between 80 to 120 securities. To gain exposure to foreign issuers, the Fund also may invest in American Depositary Receipts (“ADRs“), Global Depositary Receipts (“GDRs”) and other depositary receipts of non-U.S. listed companies.

The Subadvisor uses a bottom-up investment process driven by fundamental research conducted by its investment analysts. Under normal market conditions, the Subadvisor seeks to maintain a growth oriented focus and invest the Fund’s assets pursuant to the following core principles:

—  Earnings growth drives equity returns over the long term.

—  Early-stage and traditional growth companies provide the greatest opportunity.

—  Risk management with respect to the Fund’s portfolio should focus on avoiding losing money, rather than minimizing tracking error against the benchmark.

—  A disciplined investment process requires consistently idenitfying opportunities, evaluating potential returns and responding with timely buy/sell decisions.

PRINCIPAL RISKS

There is the risk that you may lose money on your investment. All investments carry a certain amount of risk and the Fund cannot guarantee that it will achieve its investment objective. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. Below are some of the risks of investing in the Fund.

Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars.

Emerging Markets Risk—investments in emerging markets can be subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility.

Foreign Securities Risk—securities or other investments of foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investing in securities of U.S. issuers and may result in greater price volatility.

Growth Stock Risk—growth stocks may be more sensitive to market movements because their prices tend to reflect future investor expectations rather than just current profits.

Large-Capitalization Stock Risk—the stocks of large-capitalization companies are generally more mature and may not be able to reach the same levels of growth as the stocks of small- or mid-capitalization companies.

Liquidity Risk—particular investments, such as illiquid securities, may not be able to be sold at the price the Fund would like or the Fund may have to sell them at a loss.

Market Risk—market prices of securities held by the Fund may fall rapidly or unpredictably due to a variety of factors, including changing economic, political, or market conditions. Equity investments generally have greater volatility than fixed income investments.

Political Risk—changes in the political status of any country can have profound effects on the value of investments exposed to that country.

Small- and Mid-Capitalization Stock Risk—the stocks of small- and mid-capitalization companies often have greater price volatility, lower trading volume, and less liquidity than the stocks of larger, more established companies.

PERFORMANCE

The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of a broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. To obtain updated performance information please visit www.managersinvest.com or call 800.835.3879.

Calendar Year Total Returns as of 12/31/12 (Service Class)

Best Quarter: 9.23% (4th Quarter 2011)
Worst Quarter: -17.83 (3rd Quarter 2011)

Average Annual Total Returns as of 12/31/12

Average Annual Total Returns Trilogy Global Equity Fund	1 Year	Since Inception	Inception Date
Service Class	17.37%	1.53%	Mar. 01, 2011
Service Class Return After Taxes on Distributions	17.34%	1.51%	Mar. 01, 2011
Service Class Return After Taxes on Distributions and Sale of Fund Shares	11.57%	1.36%	Mar. 01, 2011
Service Class MSCI All Country World Index (reflects no deduction for fees, expenses, or taxes)	15.83%	2.26%	Mar. 01, 2011
Institutional Class	17.35%	1.55%	Mar. 01, 2011
Institutional Class MSCI All Country World Index (reflects no deduction for fees, expenses, or taxes)	15.83%	2.26%	Mar. 01, 2011

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class shares only, and after-tax returns for Investor Class and Institutional Class shares will vary.

[1] Other Expenses have been restated to reflect current fees. The amount does not reflect expense recoupment during the prior fiscal year of pervious waivers and reimbursements equal to 0.03% that was recovered by the Managers pursuant to the Fund's contractual expense limitation agreement.

[2] The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.

[3] Managers Investment Group LLC (the "Investment Manager") has contractually agreed, through at least March 1, 2014, to waive management fees and/or reimburse Fund expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest (including interest incurred in connection with bank and custody overdrafts), shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions and other transaction costs, acquired fund fees and expenses, and extraordinary expenses) to 1.00% of the Fund's average daily net assets, subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months from the time of any waiver, reimbursement, or payment pursuant to the Fund's contractual expense limitation, the Investment Manager may recover from the Fund fees waived and expenses paid to the extent that such repayment would not cause the Fund's Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements to exceed the contractual expense limitation amount. Under such arrangement, if the maximum amount of shareholder servicing fees and distribution and service (12b-1) fees were charged to the classes under the current applicable plans, the total annual fund operating expenses (excluding the other items noted in the parenthetical above) of the Investor Class, Service Class, and Institutional Class would be 1.50%, 1.25% and 1.05%, respectively, of the average daily net assets of such classes. The contractual expense limitation may only be terminated upon termination of the Fund's investment advisory agreement with the Investment Manager or by mutual agreement between the Investment Manager and the Fund's Board of Trustees.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	MANAGERS AMG FUNDS
Prospectus Date	rr_ProspectusDate	Mar. 01, 2013
Document Creation Date	dei_DocumentCreationDate	Feb. 28, 2013

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Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	MANAGERS AMG FUNDS
Prospectus Date	rr_ProspectusDate	Mar. 01, 2013
Trilogy Global Equity Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Trilogy Global Equity Fund
Objective [Heading]	rr_ObjectiveHeading	INVESTMENT OBJECTIVE
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Trilogy Global Equity Fund's (the " Fund") investment objective is to achieve long-term capital appreciation.
Expense [Heading]	rr_ExpenseHeading	FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The tables below describes the fees and expenses that you may pay if you buy and hold shares of the Fund.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	March 1, 2014
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 78% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	78.00%
Expenses Restated to Reflect Current [Text]	rr_ExpensesRestatedToReflectCurrent	Other Expenses have been restated to reflect current fees. The amount does not reflect expense recoupment during the prior fiscal year of pervious waivers and reimbursements equal to 0.03% that was recovered by the Managers pursuant to the Fund's contractual expense limitation agreement.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]	rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees	The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.
Expense Example [Heading]	rr_ExpenseExampleHeading	EXPENSE EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund's operating expenses remain the same. The Example reflects the impact of the Fund's contractual expense limitation through March 1, 2014. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	PRINCIPAL INVESTMENT STRATEGIES
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities (generally common and preferred stocks). Additionally, under normal circumstances, the Fund will invest at least 40% of its net assets, plus the amount of any borrowing for investment purposes, in investments of issuers located outside the United States, and investments exposed to such issuers, and the Fund will invest in or have investments exposed to a minimum of three countries, including the United States. The Fund considers an issuer to be located outside the United States if the issuer maintains its principal place of business outside the United States, its securities are traded principally outside the United States, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed outside the United States or it has at least 50% of its assets outside the United States. The Fund may allocate investments across all market capitalizations, but investments generally will be in large- and medium- sized companies. Trilogy Global Advisors, L.P, (“Trilogy” or the “Subadvisor”) may invest up to 20% of the Fund’s net assets in securities of issuers located in emerging markets countries. The Subadvisor considers emerging market countries to be any country other than Canada, Luxembourg, the United States and the countries comprising the MSCI EAFE Index. The Fund considers an issuer to be located in an emerging market country if the issuer maintains its principal place of business in an emerging market country, its securities are traded in an emerging market country, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed in an emerging market country or it has at least 50% of its assets in an emerging market country. The Fund’s portfolio normally consists of between 80 to 120 securities. To gain exposure to foreign issuers, the Fund also may invest in American Depositary Receipts (“ADRs“), Global Depositary Receipts (“GDRs”) and other depositary receipts of non-U.S. listed companies. The Subadvisor uses a bottom-up investment process driven by fundamental research conducted by its investment analysts. Under normal market conditions, the Subadvisor seeks to maintain a growth oriented focus and invest the Fund’s assets pursuant to the following core principles: —  Earnings growth drives equity returns over the long term. —  Early-stage and traditional growth companies provide the greatest opportunity. —  Risk management with respect to the Fund’s portfolio should focus on avoiding losing money, rather than minimizing tracking error against the benchmark. —  A disciplined investment process requires consistently idenitfying opportunities, evaluating potential returns and responding with timely buy/sell decisions.
Risk [Heading]	rr_RiskHeading	PRINCIPAL RISKS
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	There is the risk that you may lose money on your investment. All investments carry a certain amount of risk and the Fund cannot guarantee that it will achieve its investment objective. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. Below are some of the risks of investing in the Fund. Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars. Emerging Markets Risk—investments in emerging markets can be subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility. Foreign Securities Risk—securities or other investments of foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investing in securities of U.S. issuers and may result in greater price volatility. Growth Stock Risk—growth stocks may be more sensitive to market movements because their prices tend to reflect future investor expectations rather than just current profits. Large-Capitalization Stock Risk—the stocks of large-capitalization companies are generally more mature and may not be able to reach the same levels of growth as the stocks of small- or mid-capitalization companies. Liquidity Risk—particular investments, such as illiquid securities, may not be able to be sold at the price the Fund would like or the Fund may have to sell them at a loss. Market Risk—market prices of securities held by the Fund may fall rapidly or unpredictably due to a variety of factors, including changing economic, political, or market conditions. Equity investments generally have greater volatility than fixed income investments. Political Risk—changes in the political status of any country can have profound effects on the value of investments exposed to that country. Small- and Mid-Capitalization Stock Risk—the stocks of small- and mid-capitalization companies often have greater price volatility, lower trading volume, and less liquidity than the stocks of larger, more established companies.
Risk Lose Money [Text]	rr_RiskLoseMoney	There is the risk that you may lose money on your investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	PERFORMANCE
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of a broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. To obtain updated performance information please visit www.managersinvest.com or call 800.835.3879.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of a broad-based securities market index.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	800.835.3879
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.managersinvest.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future.
Bar Chart [Heading]	rr_BarChartHeading	Calendar Year Total Returns as of 12/31/12 (Service Class)
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 9.23% (4th Quarter 2011) Worst Quarter: -17.83 (3rd Quarter 2011)
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns as of 12/31/12
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for Service Class shares only, and after-tax returns for Investor Class and Institutional Class shares will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Service Class shares only, and after-tax returns for Investor Class and Institutional Class shares will vary.
Trilogy Global Equity Fund | Investor Class
Risk/Return:	rr_RiskReturnAbstract
Management Fee	rr_ManagementFeesOverAssets	0.45%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.36%	[1]
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.07%	[2]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	none	[3]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	1.07%	[2]
1 Year	rr_ExpenseExampleYear01	109
3 Years	rr_ExpenseExampleYear03	340
5 Years	rr_ExpenseExampleYear05	590
10 Years	rr_ExpenseExampleYear10	1,306
Trilogy Global Equity Fund | Service Class
Risk/Return:	rr_RiskReturnAbstract
Management Fee	rr_ManagementFeesOverAssets	0.45%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.53%	[1]
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.99%	[2]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	none	[3]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	0.99%	[2]
1 Year	rr_ExpenseExampleYear01	101
3 Years	rr_ExpenseExampleYear03	315
5 Years	rr_ExpenseExampleYear05	547
10 Years	rr_ExpenseExampleYear10	1,213
2012	rr_AnnualReturn2012	17.37%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2011
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	9.23%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Sep. 30, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(17.83%)
1 Year	rr_AverageAnnualReturnYear01	17.37%
Since Inception	rr_AverageAnnualReturnSinceInception	1.53%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Global Equity Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Management Fee	rr_ManagementFeesOverAssets	0.45%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.36%	[1]
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.82%	[2]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	none	[3]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	0.82%	[2]
1 Year	rr_ExpenseExampleYear01	84
3 Years	rr_ExpenseExampleYear03	262
5 Years	rr_ExpenseExampleYear05	455
10 Years	rr_ExpenseExampleYear10	1,014
1 Year	rr_AverageAnnualReturnYear01	17.35%
Since Inception	rr_AverageAnnualReturnSinceInception	1.55%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Global Equity Fund | Return After Taxes on Distributions | Service Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	17.34%
Since Inception	rr_AverageAnnualReturnSinceInception	1.51%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Global Equity Fund | Return After Taxes on Distributions and Sale of Fund Shares | Service Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	11.57%
Since Inception	rr_AverageAnnualReturnSinceInception	1.36%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Global Equity Fund | MSCI All Country World Index (reflects no deduction for fees, expenses, or taxes) | Service Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	15.83%
Since Inception	rr_AverageAnnualReturnSinceInception	2.26%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Global Equity Fund | MSCI All Country World Index (reflects no deduction for fees, expenses, or taxes) | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	15.83%
Since Inception	rr_AverageAnnualReturnSinceInception	2.26%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011

[1] Other Expenses have been restated to reflect current fees. The amount does not reflect expense recoupment during the prior fiscal year of pervious waivers and reimbursements equal to 0.03% that was recovered by the Managers pursuant to the Fund's contractual expense limitation agreement.

[2] The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.

[3] Managers Investment Group LLC (the "Investment Manager") has contractually agreed, through at least March 1, 2014, to waive management fees and/or reimburse Fund expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest (including interest incurred in connection with bank and custody overdrafts), shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions and other transaction costs, acquired fund fees and expenses, and extraordinary expenses) to 1.00% of the Fund's average daily net assets, subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months from the time of any waiver, reimbursement, or payment pursuant to the Fund's contractual expense limitation, the Investment Manager may recover from the Fund fees waived and expenses paid to the extent that such repayment would not cause the Fund's Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements to exceed the contractual expense limitation amount. Under such arrangement, if the maximum amount of shareholder servicing fees and distribution and service (12b-1) fees were charged to the classes under the current applicable plans, the total annual fund operating expenses (excluding the other items noted in the parenthetical above) of the Investor Class, Service Class, and Institutional Class would be 1.50%, 1.25% and 1.05%, respectively, of the average daily net assets of such classes. The contractual expense limitation may only be terminated upon termination of the Fund's investment advisory agreement with the Investment Manager or by mutual agreement between the Investment Manager and the Fund's Board of Trustees.

XML

Document and Entity Information	12 Months Ended
	Mar. 01, 2013
Risk/Return:
Document Type	485BPOS
Document Period End Date	Oct. 31, 2012
Registrant Name	MANAGERS AMG FUNDS
Central Index Key	0001089951
Amendment Flag	false
Document Creation Date	Feb. 28, 2013
Document Effective Date	Mar. 01, 2013
Prospectus Date	Mar. 01, 2013

XML

Trilogy International Small Cap Fund

Trilogy International Small Cap Fund

INVESTMENT OBJECTIVE

The Trilogy International Small Cap Fund's (the "Fund" or "International Small Cap Fund") investment objective is to seek long-term capital appreciation.

FEES AND EXPENSES OF THE FUND

The tables below describes the fees and expenses that you may pay if you buy and hold shares of the Fund.

Shareholder Fees
(fees paid directly from your investment)

Shareholder Fees Trilogy International Small Cap Fund	Investor Class	Service Class	Institutional Class
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	2.00%	2.00%	2.00%

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses Trilogy International Small Cap Fund		Investor Class	Service Class	Institutional Class
Management Fee		1.00%	1.00%	1.00%
Distribution and Service (12b-1) Fees		0.25%	none	none
Other Expenses		0.82%	1.01%	0.82%
Total Annual Fund Operating Expenses	[1]	2.07%	2.01%	1.82%
Fee Waiver and Expense Reimbursements	[2]	(0.72%)	(0.72%)	(0.72%)
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	[1]	1.35%	1.29%	1.10%

EXPENSE EXAMPLE

This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund's operating expenses remain the same. The Example reflects the impact of the Fund's contractual expense limitation through March 1, 2014. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:

Expense Example Trilogy International Small Cap Fund (USD $)	1 Year	3 Years	5 Years	10 Years
Investor Class	137	579	1,047	2,343
Service Class	131	561	1,016	2,280
Institutional Class	112	502	918	2,078

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 56% of the average value of its portfolio.

PRINCIPAL INVESTMENT STRATEGIES

Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities (generally common and preferred stocks) of small market capitalization companies ("small cap companies"). Additionally, under normal circumstances, the Fund will invest at least 40% of its net assets, plus the amount of any borrowing for investment purposes, in investments of issuers located outside the United States, and investments exposed to such issuers, and the Fund will invest in or have investments exposed to a minimum of three countries, including the United States. The Fund considers an issuer to be located outside the United States if the issuer maintains its principal place of business outside the United States, its securities are traded principally outside the United States, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed outside the United States or it has at least 50% of its assets outside the United States.

The Fund primarily invests in non-U.S. small cap companies, allocating investments across different countries and regions. The Subadvisor considers non-U.S. small cap companies to be those with market capitalizations in the range of the MSCI All Country World ex-U.S. Small Cap Index (between $3.53 million and $4.39 billion as of the latest reconstitution of the Index on December 1, 2012). The Fund may invest in securities of issuers located in emerging markets countries. The Fund's Subadvisor considers emerging market countries to be any country other than Canada, Luxembourg, the United States and the countries comprising the MSCI EAFE Index. The Fund's portfolio normally consists of between 40 to 100 securities. To gain exposure to foreign issuers, the Fund also may invest in American Depositary Receipts ("ADRs"), Global Depoisitary Receipts ("GDRs") and other depositary receipts of non-U.S. listed companies.

The Subadvisor uses a bottom-up investment process driven by fundamental research conducted by its investment analysts. Under normal market conditions, the Subadvisor seeks to maintain a growth oriented focus and invest the Fund's assets pursuant to the following core principles:

—  Earnings growth drives equity returns over the long term.

—  Early-stage and traditional growth companies provide the greatest opportunity.

—  Risk management with respect to the Fund's portfolio should focus on avoiding losing money, rather than minimizing tracking error against the benchmark.

—  A disciplined investment process requires consistently identifying opportunities, evaluating potential returns and responding with timely buy/sell decisions.

PRINCIPAL RISKS

There is the risk that you may lose money on your investment. All investments carry a certain amount of risk and the Fund cannot guarantee that it will achieve its investment objective. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation ("FDIC") or any other government agency. Below are some of the risks of investing in the Fund.

Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars.

Derivatives Risk—the complexity and rapidly changing structure of derivatives markets may increase the possibility of market losses.

Emerging Markets Risk—investments in emerging markets can be subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility.

Foreign Securities Risk—securities or other investments of foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investing in securities of U.S. issuers and may result in greater price volatility.

Growth Stock Risk—growth stocks may be more sensitive to market movements because their prices tend to reflect future investor expectations rather than just current profits.

Liquidity Risk—particular investments, such as illiquid securities, may not be able to be sold at the price the Fund would like or the Fund may have to sell them at a loss.

Market Risk—market prices of securities held by the Fund may fall rapidly or unpredictably due to a variety of factors, including changing economic, political, or market conditions. Equity investments generally have greater volatility than fixed income investments.

Political Risk—changes in the political status of any country can have profound effects on the value of investments exposed to that country.

Small-Capitalization Stock Risk—the stocks of small-capitalization companies often have greater price volatility, lower trading volume, and less liquidity than the stocks of larger, more established companies.

PERFORMANCE

The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of broad based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. To obtain updated performance information please visit www.managersinvest.com or call 800.835.3879.

Calendar Year Total Returns as of 12/31/2012 (Institutional Class)

Best Quarter: 5.54 (4th Quarter 2011)
Worst Quarter: -25.20 (3rd Quarter 2011)

Average Annual Total Returns as of 12/31/12

Average Annual Total Returns Trilogy International Small Cap Fund	1 Year	Since Inception	Inception Date
Investor Class	21.70%	(1.70%)	Jul. 15, 2011
Investor Class MSCI All Country World Index Ex US Small Cap (reflects no deduction for fees, expenses, or taxes)	18.52%	(2.89%)	Jul. 15, 2011
Service Class	21.86%	(2.60%)	Mar. 01, 2011
Service Class MSCI All Country World Index Ex US Small Cap (reflects no deduction for fees, expenses, or taxes)	18.52%	(2.64%)	Mar. 01, 2011
Institutional Class	21.90%	(2.50%)	Mar. 01, 2011
Institutional Class Return After Taxes on Distributions	21.78%	(2.49%)	Mar. 01, 2011
Institutional Class Return After Taxes on Distributions and Sale of Fund Shares	14.68%	(1.97%)	Mar. 01, 2011
Institutional Class MSCI All Country World Index Ex US Small Cap (reflects no deduction for fees, expenses, or taxes)	18.52%	(2.64%)	Mar. 01, 2011

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Institutional Class shares only, and after-tax returns for Service Class and Investor Class shares will vary.

[1] The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.

[2] Managers Investment Group LLC (the "Investment Manager") has contractually agreed, through at least March 1, 2014, to waive management fees and/or reimburse Fund expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest (including interest incurred in connection with bank and custody overdrafts), shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions and other transaction costs, acquired fund fees and expenses, and extraordinary expenses) to 1.10% of the Fund's average daily net assets, subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months from the time of any waiver, reimbursement, or payment pursuant to the Fund's contractual expense limitation, the Investment Manager may recover from the Fund fees waived and expenses paid to the extent that such repayment would not cause the Fund's Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements to exceed the contractual expense limitation amount. Under such arrangement, if the maximum amount of shareholder servicing fees and distribution and service (12b-1) fees were charged to the classes under the current applicable plans, the total annual fund operating expenses (excluding the other items noted in the parenthetical above) of the Investor Class, Service Class, and Institutional Class would be 1.60%, 1.35% and 1.15%, respectively, of the average daily net assets of such classes. The contractual expense limitation may only be terminated upon termination of the Fund's investment advisory agreement with the Investment Manager or by mutual agreement between the Investment Manager and the Fund's Board of Trustees.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	MANAGERS AMG FUNDS
Prospectus Date	rr_ProspectusDate	Mar. 01, 2013
Trilogy Emerging Markets Equity Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Trilogy Emerging Markets Equity Fund
Objective [Heading]	rr_ObjectiveHeading	INVESTMENT OBJECTIVE
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Trilogy Emerging Markets Equity Fund's (the "Fund" or "Emerging Markets Equity Fund") investment objective is to seek long-term capital appreciation.
Expense [Heading]	rr_ExpenseHeading	FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The tables below describe the fees and expenses that you may pay if you buy and hold shares of the Fund.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	March 1, 2014
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 32% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	32.00%
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]	rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees	The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.
Expense Example [Heading]	rr_ExpenseExampleHeading	EXPENSE EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund's operating expenses remain the same. The Example reflects the impact of the Fund's contractual expense limitation through March 1, 2014. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	PRINCIPAL INVESTMENT STRATEGIES
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities (generally common and preferred stocks) of issuers located in emerging market countries. The Fund may allocate investments across different emerging markets countries. The Subadvisor considers emerging market countries to be any country other than Canada, Luxembourg, the United States and the countries comprising the MSCI EAFE Index. The Fund considers an issuer to be located in an emerging market country if the issuer maintains its principal place of business in an emerging market country, its securities are traded principally in an emerging market country, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed in an emerging market country or it has at least 50% of its assets in an emerging market country. The Fund's portfolio normally consists of between 60 to 120 securities. To gain exposure to foreign issuers, the Fund also may invest in American Depositary Receipts ("ADRs"), Global Depositary Receipts ("GDRs") and other depositary receipts of non-U.S. listed companies. The Subadvisor uses a bottom-up investment process driven by fundamental research conducted by its investment analysts. Under normal market conditions, the Subadvisor seeks to maintain a growth oriented focus and invest the Fund's assets pursuant to the following core principles: —  Earnings growth drives equity returns over the long term. —  Early-stage and traditional growth companies provide the greatest opportunity. —  Risk management with respect to the Fund's portfolio should focus on avoiding losing money, rather than minimizing tracking error against the benchmark. —  A disciplined investment process requires consistently identifying opportunities, evaluating potential returns and responding with timely buy/sell decisions.
Risk [Heading]	rr_RiskHeading	PRINCIPAL RISKS
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	There is the risk that you may lose money on your investment. All investments carry a certain amount of risk and the Fund cannot guarantee that it will achieve its investment objective. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation (“FDIC”) or any other government agency. Below are some of the risks of investing in the Fund. Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars. Derivatives Risk—the complexity and rapidly changing structure of derivatives markets may increase the possibility of market losses. Emerging Markets Risk—investments in emerging markets can be subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility. Foreign Securities Risk—securities or other investments of foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investing in securities of U.S. issuers and may result in greater price volatility. Growth Stock Risk—growth stocks may be more sensitive to market movements because their prices tend to reflect future investor expectations rather than just current profits. Large-Capitalization Stock Risk—the stocks of large-capitalization companies are generally more mature and may not be able to reach the same levels of growth as the stocks of small- or mid-capitalization companies. Liquidity Risk—particular investments, such as illiquid securities, may not be able to be sold at the price the Fund would like or the Fund may have to sell them at a loss. Market Risk—market prices of securities held by the Fund may fall rapidly or unpredictably due to a variety of factors, including changing economic, political, or market conditions. Equity investments generally have greater volatility than fixed income investments. Political Risk—changes in the political status of any country can have profound effects on the value of investments exposed to that country. Small- and Mid-Capitalization Stock Risk—the stocks of small- and mid-capitalization companies often have greater price volatility, lower trading volume, and less liquidity than the stocks of larger, more established companies.
Risk Lose Money [Text]	rr_RiskLoseMoney	There is the risk that you may lose money on your investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation ("FDIC") or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	PERFORMANCE
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of broad-based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. Because the Fund's Investor Class shares have not operated for a full calendar year, performance history for this share class is not available. Investor Class shares would have similar annual returns as Service Class and Institutional Class shares because all of the classes are invested in the same portfolio of securities. However, Investor Class shares are subject to different expenses than Service Class and Institutional Class shares, and Investor Class share performance would vary to that extent. To obtain updated performance information please visit www.managersinvest.com or call 800.835.3879.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of broad-based securities market index.
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	Because the Fund's Investor Class shares have not operated for a full calendar year, performance history for this share class is not available.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	800.835.3879
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.managersinvest.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future.
Bar Chart [Heading]	rr_BarChartHeading	Calendar Year Total Returns as of (12/31/12) Institutional Class
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 4.70 (4th Quarter 2012) Worst Quarter: 24.01 (3rd Quarter 2011)
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns as of 12/31/12
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for Institutional Class shares only, and after-tax returns for Service Class and Investor Class shares will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Institutional Class shares only, and after-tax returns for Service Class and Investor Class shares will vary.
Trilogy Emerging Markets Equity Fund | Investor Class
Risk/Return:	rr_RiskReturnAbstract
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	rr_RedemptionFeeOverRedemption	2.00%
Management Fee	rr_ManagementFeesOverAssets	0.70%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.35%
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.31%	[1]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	none	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	1.31%	[1]
1 Year	rr_ExpenseExampleYear01	133
3 Years	rr_ExpenseExampleYear03	415
5 Years	rr_ExpenseExampleYear05	718
10 Years	rr_ExpenseExampleYear10	1,579
Trilogy Emerging Markets Equity Fund | Service Class
Risk/Return:	rr_RiskReturnAbstract
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	rr_RedemptionFeeOverRedemption	2.00%
Management Fee	rr_ManagementFeesOverAssets	0.70%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.55%
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.26%	[1]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	none	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	1.26%	[1]
1 Year	rr_ExpenseExampleYear01	128
3 Years	rr_ExpenseExampleYear03	400
5 Years	rr_ExpenseExampleYear05	692
10 Years	rr_ExpenseExampleYear10	1,523
1 Year	rr_AverageAnnualReturnYear01	17.37%
Since Inception	rr_AverageAnnualReturnSinceInception	1.53%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Emerging Markets Equity Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	rr_RedemptionFeeOverRedemption	2.00%
Management Fee	rr_ManagementFeesOverAssets	0.70%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.35%
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	none	[1]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	none	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	1.06%	[1]
1 Year	rr_ExpenseExampleYear01	108
3 Years	rr_ExpenseExampleYear03	337
5 Years	rr_ExpenseExampleYear05	585
10 Years	rr_ExpenseExampleYear10	1,294
2012	rr_AnnualReturn2012	15.52%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2012
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	4.70%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Sep. 30, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	24.01%
1 Year	rr_AverageAnnualReturnYear01	15.52%
Since Inception	rr_AverageAnnualReturnSinceInception	(5.18%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Emerging Markets Equity Fund | Return After Taxes on Distributions | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	15.60%
Since Inception	rr_AverageAnnualReturnSinceInception	(5.14%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Emerging Markets Equity Fund | Return After Taxes on Distributions and Sale of Fund Shares | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	10.42%
Since Inception	rr_AverageAnnualReturnSinceInception	(4.29%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Emerging Markets Equity Fund | MSCI Emerging Markets Index (reflects no deduction for fees, expenses, or taxes) | Service Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	18.22%
Since Inception	rr_AverageAnnualReturnSinceInception	0.15%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy Emerging Markets Equity Fund | MSCI Emerging Markets Index (reflects no deduction for fees, expenses, or taxes) | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	18.22%
Since Inception	rr_AverageAnnualReturnSinceInception	0.15%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011

[1] The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.

[2] Managers Investment Group LLC (the "Investment Manager") has contractually agreed, through at least March 1, 2014, to waive management fees and/or reimburse Fund expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest, shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions, acquired fund fees and expenses, and extraordinary items) to 1.05% of the Fund's average daily net assets, subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months from the time of any waiver, reimbursement, or payment pursuant to the Fund's contractual expense limitation, the Investment Manager may recover from the Fund fees waived and expenses paid to the extent that such repayment would not cause the Fund's Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements to exceed the contractual expense limitation amount. Under such arrangement, if the maximum amount of shareholder servicing fees and distribution and service (12b-1) fees were charged to the classes under the current applicable plans, the total annual fund operating expenses (excluding the other items noted in the parenthetical above) of the Investor Class, Service Class, and Institutional Class would be 1.55%, 1.30% and 1.05% respectively, of the average daily net assets of such classes. The contractual expense limitation may only be terminated upon termination of the Fund's investment advisory agreement with the Investment Manager or by mutual agreement between the Investment Manager and the Fund's Board of Trustees.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	MANAGERS AMG FUNDS
Prospectus Date	rr_ProspectusDate	Mar. 01, 2013
Trilogy International Small Cap Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Trilogy International Small Cap Fund
Objective [Heading]	rr_ObjectiveHeading	INVESTMENT OBJECTIVE
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Trilogy International Small Cap Fund's (the "Fund" or "International Small Cap Fund") investment objective is to seek long-term capital appreciation.
Expense [Heading]	rr_ExpenseHeading	FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The tables below describes the fees and expenses that you may pay if you buy and hold shares of the Fund.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	March 1, 2014
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	PORTFOLIO TURNOVER
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 56% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	56.00%
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]	rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees	The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.
Expense Example [Heading]	rr_ExpenseExampleHeading	EXPENSE EXAMPLE
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example will help you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example makes certain assumptions. It assumes that you invest $10,000 as an initial investment in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. It also assumes that your investment has a 5% total return each year and the Fund's operating expenses remain the same. The Example reflects the impact of the Fund's contractual expense limitation through March 1, 2014. Although your actual costs may be higher or lower, based on the above assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	PRINCIPAL INVESTMENT STRATEGIES
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities (generally common and preferred stocks) of small market capitalization companies ("small cap companies"). Additionally, under normal circumstances, the Fund will invest at least 40% of its net assets, plus the amount of any borrowing for investment purposes, in investments of issuers located outside the United States, and investments exposed to such issuers, and the Fund will invest in or have investments exposed to a minimum of three countries, including the United States. The Fund considers an issuer to be located outside the United States if the issuer maintains its principal place of business outside the United States, its securities are traded principally outside the United States, or it derives at least 50% of its revenues or profits from goods produced or sold, investments made, or services performed outside the United States or it has at least 50% of its assets outside the United States. The Fund primarily invests in non-U.S. small cap companies, allocating investments across different countries and regions. The Subadvisor considers non-U.S. small cap companies to be those with market capitalizations in the range of the MSCI All Country World ex-U.S. Small Cap Index (between $3.53 million and $4.39 billion as of the latest reconstitution of the Index on December 1, 2012). The Fund may invest in securities of issuers located in emerging markets countries. The Fund's Subadvisor considers emerging market countries to be any country other than Canada, Luxembourg, the United States and the countries comprising the MSCI EAFE Index. The Fund's portfolio normally consists of between 40 to 100 securities. To gain exposure to foreign issuers, the Fund also may invest in American Depositary Receipts ("ADRs"), Global Depoisitary Receipts ("GDRs") and other depositary receipts of non-U.S. listed companies. The Subadvisor uses a bottom-up investment process driven by fundamental research conducted by its investment analysts. Under normal market conditions, the Subadvisor seeks to maintain a growth oriented focus and invest the Fund's assets pursuant to the following core principles: —  Earnings growth drives equity returns over the long term. —  Early-stage and traditional growth companies provide the greatest opportunity. —  Risk management with respect to the Fund's portfolio should focus on avoiding losing money, rather than minimizing tracking error against the benchmark. —  A disciplined investment process requires consistently identifying opportunities, evaluating potential returns and responding with timely buy/sell decisions.
Risk [Heading]	rr_RiskHeading	PRINCIPAL RISKS
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	There is the risk that you may lose money on your investment. All investments carry a certain amount of risk and the Fund cannot guarantee that it will achieve its investment objective. An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation ("FDIC") or any other government agency. Below are some of the risks of investing in the Fund. Currency Risk—fluctuations in exchange rates may affect the total loss or gain on a non-U.S. dollar investment when converted back to U.S. dollars. Derivatives Risk—the complexity and rapidly changing structure of derivatives markets may increase the possibility of market losses. Emerging Markets Risk—investments in emerging markets can be subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility. Foreign Securities Risk—securities or other investments of foreign issuers involve additional risks (such as risks arising from less frequent trading, changes in political or social conditions, and less publicly available information about non-U.S. issuers) that differ from those associated with investing in securities of U.S. issuers and may result in greater price volatility. Growth Stock Risk—growth stocks may be more sensitive to market movements because their prices tend to reflect future investor expectations rather than just current profits. Liquidity Risk—particular investments, such as illiquid securities, may not be able to be sold at the price the Fund would like or the Fund may have to sell them at a loss. Market Risk—market prices of securities held by the Fund may fall rapidly or unpredictably due to a variety of factors, including changing economic, political, or market conditions. Equity investments generally have greater volatility than fixed income investments. Political Risk—changes in the political status of any country can have profound effects on the value of investments exposed to that country. Small-Capitalization Stock Risk—the stocks of small-capitalization companies often have greater price volatility, lower trading volume, and less liquidity than the stocks of larger, more established companies.
Risk Lose Money [Text]	rr_RiskLoseMoney	There is the risk that you may lose money on your investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit or obligation of any bank, is not endorsed or guaranteed by any bank, and is not insured by the Federal Deposit Insurance Corporation ("FDIC") or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	PERFORMANCE
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of broad based securities market index. As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future. To obtain updated performance information please visit www.managersinvest.com or call 800.835.3879.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The following performance information illustrates the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's performance compares to that of broad based securities market index.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	800.835.3879
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.managersinvest.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	As always, past performance of the Fund (before and after taxes) is not an indication of how the Fund will perform in the future.
Bar Chart [Heading]	rr_BarChartHeading	Calendar Year Total Returns as of 12/31/2012 (Institutional Class)
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter: 5.54 (4th Quarter 2011) Worst Quarter: -25.20 (3rd Quarter 2011)
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns as of 12/31/12
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for Institutional Class shares only, and after-tax returns for Service Class and Investor Class shares will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Institutional Class shares only, and after-tax returns for Service Class and Investor Class shares will vary.
Trilogy International Small Cap Fund | Investor Class
Risk/Return:	rr_RiskReturnAbstract
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	rr_RedemptionFeeOverRedemption	2.00%
Management Fee	rr_ManagementFeesOverAssets	1.00%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.82%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	2.07%	[1]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.72%)	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	1.35%	[1]
1 Year	rr_ExpenseExampleYear01	137
3 Years	rr_ExpenseExampleYear03	579
5 Years	rr_ExpenseExampleYear05	1,047
10 Years	rr_ExpenseExampleYear10	2,343
1 Year	rr_AverageAnnualReturnYear01	21.70%
Since Inception	rr_AverageAnnualReturnSinceInception	(1.70%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 15, 2011
Trilogy International Small Cap Fund | Service Class
Risk/Return:	rr_RiskReturnAbstract
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	rr_RedemptionFeeOverRedemption	2.00%
Management Fee	rr_ManagementFeesOverAssets	1.00%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	1.01%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	2.01%	[1]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.72%)	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	1.29%	[1]
1 Year	rr_ExpenseExampleYear01	131
3 Years	rr_ExpenseExampleYear03	561
5 Years	rr_ExpenseExampleYear05	1,016
10 Years	rr_ExpenseExampleYear10	2,280
1 Year	rr_AverageAnnualReturnYear01	21.86%
Since Inception	rr_AverageAnnualReturnSinceInception	(2.60%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy International Small Cap Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Redemption/Exchange Fee (as a percentage of the amount redeemed, if applicable, within 60 days of purchase)	rr_RedemptionFeeOverRedemption	2.00%
Management Fee	rr_ManagementFeesOverAssets	1.00%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.82%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.82%	[1]
Fee Waiver and Expense Reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(0.72%)	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements	rr_NetExpensesOverAssets	1.10%	[1]
1 Year	rr_ExpenseExampleYear01	112
3 Years	rr_ExpenseExampleYear03	502
5 Years	rr_ExpenseExampleYear05	918
10 Years	rr_ExpenseExampleYear10	2,078
2012	rr_AnnualReturn2012	21.90%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2011
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	5.54%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Sep. 30, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(25.20%)
1 Year	rr_AverageAnnualReturnYear01	21.90%
Since Inception	rr_AverageAnnualReturnSinceInception	(2.50%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy International Small Cap Fund | Return After Taxes on Distributions | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	21.78%
Since Inception	rr_AverageAnnualReturnSinceInception	(2.49%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy International Small Cap Fund | Return After Taxes on Distributions and Sale of Fund Shares | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	14.68%
Since Inception	rr_AverageAnnualReturnSinceInception	(1.97%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy International Small Cap Fund | MSCI All Country World Index Ex US Small Cap (reflects no deduction for fees, expenses, or taxes) | Investor Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	18.52%
Since Inception	rr_AverageAnnualReturnSinceInception	(2.89%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Jul. 15, 2011
Trilogy International Small Cap Fund | MSCI All Country World Index Ex US Small Cap (reflects no deduction for fees, expenses, or taxes) | Service Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	18.52%
Since Inception	rr_AverageAnnualReturnSinceInception	(2.64%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011
Trilogy International Small Cap Fund | MSCI All Country World Index Ex US Small Cap (reflects no deduction for fees, expenses, or taxes) | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	18.52%
Since Inception	rr_AverageAnnualReturnSinceInception	(2.64%)
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2011

[1] The Total Annual Fund Operating Expenses and Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements do not correlate to the ratios of expenses to average net assets in the Financial Highlights section of the Fund's Prospectus. The ratios reflect only the operating expenses of the Fund and do not include fees and expenses of any acquired funds.

[2] Managers Investment Group LLC (the "Investment Manager") has contractually agreed, through at least March 1, 2014, to waive management fees and/or reimburse Fund expenses in order to limit Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements (exclusive of taxes, interest (including interest incurred in connection with bank and custody overdrafts), shareholder servicing fees, distribution and service (12b-1) fees, brokerage commissions and other transaction costs, acquired fund fees and expenses, and extraordinary expenses) to 1.10% of the Fund's average daily net assets, subject to later reimbursement by the Fund in certain circumstances. In general, for a period of up to 36 months from the time of any waiver, reimbursement, or payment pursuant to the Fund's contractual expense limitation, the Investment Manager may recover from the Fund fees waived and expenses paid to the extent that such repayment would not cause the Fund's Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursements to exceed the contractual expense limitation amount. Under such arrangement, if the maximum amount of shareholder servicing fees and distribution and service (12b-1) fees were charged to the classes under the current applicable plans, the total annual fund operating expenses (excluding the other items noted in the parenthetical above) of the Investor Class, Service Class, and Institutional Class would be 1.60%, 1.35% and 1.15%, respectively, of the average daily net assets of such classes. The contractual expense limitation may only be terminated upon termination of the Fund's investment advisory agreement with the Investment Manager or by mutual agreement between the Investment Manager and the Fund's Board of Trustees.