S000009904 [Member] Investment Risks - AMG Veritas Global Focus Fund	Oct. 31, 2025
Management Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Management Risk—because the Fund is an actively managed investment portfolio, security selection or focus on securities in a particular style, market sector or group of companies may cause the Fund to incur losses or underperform relative to its benchmarks or other funds with a similar investment objective. There can be no guarantee that the Subadviser’s investment techniques and risk analysis will produce the desired result.
Foreign Investment Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Foreign Investment Risk—investments in 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 investments in U.S. issuers and may result in greater price volatility.
Focused Investment Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Focused Investment Risk—to the extent the Fund invests a substantial portion of its assets in a relatively small number of securities or a particular market, industry, group of industries, country, region, group of countries, asset class or sector, it generally will be subject to greater risk than a fund that invests in a more diverse investment portfolio. In addition, the value of the Fund would be more susceptible to any single economic, market, political or regulatory occurrence affecting, for example, that particular market, industry, region or sector.
Value Stock Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Value Stock Risk—value stocks may perform differently from the market as a whole and may be undervalued by the market for a long period of time.
Currency Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	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 and exposure to non-U.S. currencies may subject the Fund to the risk that those currencies will decline in value relative to the U.S. dollar.
Emerging Markets Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Emerging Markets Risk—investments in emerging markets are subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility. Such additional risks include the risk that markets in emerging market countries are typically less developed and less liquid than markets in developed countries and such markets are subjected to increased economic, political, or regulatory uncertainties.
High Cash Balance Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	High Cash Balance Risk— when the Fund has a significant cash balance for a sustained period, the benefit to the Fund of any market upswing may likely be reduced, and the Fund’s performance may be adversely affected.
Large Capitalization Stock Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	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 [Member]
Prospectus [Line Items]
Risk [Text Block]	Liquidity Risk—the Fund may not be able to dispose of particular investments, such as illiquid securities, readily at favorable times or prices or the Fund may have to sell them at a loss.
Political Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Political Risk—changes in the general political and social environment of a country can have substantial effects on the value of investments exposed to that country.
Sector Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	Sector Risk—issuers and companies that are in similar industry sectors may be similarly affected by particular economic or market events; to the extent the Fund has substantial holdings within a particular sector, the risks associated with that sector increase. Stocks in the healthcare and industrials sectors may comprise a significant portion of the Fund's portfolio. Stocks in the healthcare sector may be affected by technological obsolescence, changes in regulatory approval policies for drugs, medical devices or procedures and changes in governmental and private payment systems. The industrials sector may be affected by general economic trends, including employment, economic growth and interest rates, changes in consumer confidence and spending, government regulation, commodity prices and competitive pressures.
Small and Mid Capitalization Stock Risk [Member]
Prospectus [Line Items]
Risk [Text Block]	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.
Market Risks [Member]
Prospectus [Line Items]
Risk [Text Block]	Market Risk—market prices of investments held by the Fund may fall rapidly or unpredictably due to a variety of factors, including economic or market conditions, or other factors including terrorism, war, natural disasters and the spread of infectious illness or other public health issues, including epidemics or pandemics, or in response to events that affect particular industries or companies. In addition, unexpected political, regulatory, trade and diplomatic events within the United States and abroad may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.
Risk Lose Money [Member]
Prospectus [Line Items]
Risk [Text Block]	There is the risk that you may lose money on your investment.
Risk Not Insured Depository Institution [Member]
Prospectus [Line Items]
Risk [Text Block]	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.
Risk Nondiversified Status [Member]
Prospectus [Line Items]
Risk [Text Block]	Non-Diversified Fund Risk—the Fund is non-diversified and therefore a greater percentage of holdings may be focused in a small number of issuers or a single issuer, which can place the Fund at greater risk. Notwithstanding the Fund’s status as a “non-diversified” investment company under the Investment Company Act of 1940 (the “1940 Act”), the Fund intends to qualify each year as a regulated investment company accorded favorable tax treatment under the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”), which imposes its own diversification requirements that are less restrictive than the requirements applicable to “diversified” investment companies under the 1940 Act. The Fund’s intention to qualify as a regulated investment company may limit its pursuit of its investment strategy and its investment strategy could limit its ability to so qualify.

S000009904 [Member] Investment Risks - AMG Veritas Global Focus Fund

Oct. 31, 2025

Management Risk—because the Fund is an actively managed investment portfolio, security selection or focus on securities in a particular style, market sector or group of companies may cause the Fund to incur losses or underperform relative to its benchmarks or other funds with a similar investment objective. There

can be no guarantee that the Subadviser’s investment techniques and risk analysis will produce the desired result.

Foreign Investment Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Foreign Investment Risk—investments in 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 investments in U.S. issuers and may result in greater price volatility.

Focused Investment Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Focused Investment Risk—to the extent the Fund invests a substantial portion of its assets in a relatively small number of securities or a particular market, industry, group of industries, country, region, group of countries, asset class or sector, it generally will be subject to greater risk than a fund that invests in a more diverse investment portfolio. In addition, the value of the Fund would be more susceptible to any single economic, market, political or regulatory occurrence affecting, for example, that particular market, industry, region or sector.

Value Stock Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Value Stock Risk—value stocks may perform differently from the market as a whole and may be undervalued by the market for a long period of time.

Currency Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

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 and exposure to non-U.S. currencies may subject the Fund to the risk that those currencies will decline in value relative to the U.S. dollar.

Emerging Markets Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Emerging Markets Risk—investments in emerging markets are subject to the general risks of foreign investments, as well as additional risks which can result in greater price volatility. Such additional risks include the risk that markets in emerging market countries are typically less developed and less liquid than markets in developed countries and such markets are subjected to increased economic, political, or regulatory uncertainties.

High Cash Balance Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

High Cash Balance Risk— when the Fund has a significant cash balance for a sustained period, the benefit to the Fund of any market upswing may likely be reduced, and the Fund’s performance may be adversely affected.

Large Capitalization Stock Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

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 [Member]

Prospectus [Line Items]

Risk [Text Block]

Liquidity Risk—the Fund may not be able to dispose of particular investments, such as illiquid securities, readily at favorable times or prices or the Fund may have to sell them at a loss.

Political Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Political Risk—changes in the general political and social environment of a country can have substantial effects on the value of investments exposed to that country.

Sector Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

Sector Risk—issuers and companies that are in similar industry sectors may be similarly affected by particular economic or market events; to the extent the Fund has substantial holdings within a particular sector, the risks associated with that sector increase. Stocks in the healthcare and industrials sectors may comprise a significant portion of the Fund's portfolio. Stocks in the healthcare sector may be affected by technological obsolescence, changes in regulatory approval policies for drugs, medical devices or procedures and changes in governmental and private payment systems. The industrials sector may be affected by general economic trends, including employment, economic growth and interest rates, changes in consumer confidence and spending, government regulation, commodity prices and competitive pressures.

Small and Mid Capitalization Stock Risk [Member]

Prospectus [Line Items]

Risk [Text Block]

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.

Market Risks [Member]

Prospectus [Line Items]

Risk [Text Block]

Market Risk—market prices of investments held by the Fund may fall rapidly or unpredictably due to a variety of factors, including economic or market conditions, or other factors including terrorism, war, natural disasters and the spread of infectious illness or other public health issues, including epidemics or pandemics, or in response to events that affect particular industries or companies. In addition, unexpected political, regulatory, trade and diplomatic events within the United States and abroad may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree.

Risk Lose Money [Member]

Prospectus [Line Items]

Risk [Text Block]

There is the risk that you may lose money on your investment.

Risk Not Insured Depository Institution [Member]

Prospectus [Line Items]

Risk [Text Block]

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.

Risk Nondiversified Status [Member]

Prospectus [Line Items]

Risk [Text Block]

Non-Diversified Fund Risk—the Fund is non-diversified and therefore a greater percentage of holdings may be focused in a small number of issuers or a single issuer, which can place the Fund at greater risk. Notwithstanding the Fund’s status as a “non-diversified” investment company under the Investment Company Act of 1940 (the “1940 Act”), the Fund intends to qualify each year as a regulated investment company accorded favorable tax treatment under the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”), which imposes its own diversification requirements that are less

restrictive than the requirements applicable to “diversified” investment companies under the 1940 Act. The Fund’s intention to qualify as a regulated investment company may limit its pursuit of its investment strategy and its investment strategy could limit its ability to so qualify.