Label

Element

Value

Risk/Return:

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Registrant Name

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TRANSAMERICA FUNDS

Prospectus Date

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Mar. 01, 2019

Class I | Transamerica International Small Cap Value

Risk/Return:

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Risk/Return [Heading]

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<b>Transamerica International Small Cap Value </b>

Objective [Heading]

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<b>Investment Objective:</b>

Objective, Primary [Text Block]

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Seeks maximum long-term total return.

Expense [Heading]

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<b>Fees and Expenses:</b>

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy and hold Class I shares of the fund.

Shareholder Fees Caption [Text]

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<b>Shareholder Fees (fees paid directly from your investment) </b>

Operating Expenses Caption [Text]

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

Portfolio Turnover [Heading]

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<b>Portfolio Turnover:</b>

Portfolio Turnover [Text Block]

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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 portfolio turnover rate for the fund was 20% of the average value of its portfolio.

Portfolio Turnover, Rate

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20.00%

Expense Example [Heading]

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<b>Example:</b>

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all shares at the end of those periods (unless otherwise indicated). The Example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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<b>Principal Investment Strategies:</b>

Strategy Narrative [Text Block]

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The fund’s sub-adviser, Thompson, Siegel & Walmsley LLC (the “sub-adviser”), invests under normal circumstances, at least 80% of the fund’s net assets (plus the amount of borrowings, if any, for investment purposes) in small-capitalization companies. The fund considers small-cap companies to be those with market capitalizations between $200 million and $8 billion at the time of investment. The fund primarily invests in equity securities of small-cap companies located outside the United States. The sub-adviser will seek stocks that it believes are undervalued. The fund expects capital growth to be the predominant component of its total return.

Generally, the fund will invest primarily in common stocks of companies listed on foreign securities exchanges, but it may also invest in depositary receipts including American Depositary Receipts (“ADRs”), Global Depositary Receipts (“GDRs”) and European Depositary Receipts (“EDRs”). Although the fund will emphasize small cap companies, it may invest in companies of varying sizes as measured by assets, sales or market capitalization. The fund will invest primarily in securities of companies domiciled in developed markets, but may invest up to 25% of its assets in securities of companies in emerging markets. It is expected that investments will generally be diversified throughout the world and within markets in an effort to moderate specific country and currency risks.

The sub-adviser employs a relative value process utilizing a combination of quantitative and qualitative methods based on a four-factor valuation screen designed to outperform the MSCI Europe, Australasia and Far East (“EAFE”) Small Cap Index. The sub-adviser’s analysts also perform rigorous fundamental analysis. A portfolio composed of approximately 80-120 securities is selected as a result of this process.

The sub-adviser employs a consistent sell discipline, regularly reviewing the investment thesis and valuation for each stock and selling those where the catalyst is no longer valid or where another stock presents a significantly better combination of risk and reward. The sub-adviser trims and reviews for elimination any stock that suffers a significant negative earnings revision and eliminates any stock whose market capitalization reaches twice the maximum market cap of the MSCI EAFE Small Cap Index.

Risk [Heading]

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<b>Principal Risks:</b>

Risk Narrative [Text Block]

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Risk is inherent in all investing. Many factors affect the fund's performance. The value of your investment in the fund, as well as the amount of return you receive on your investment, may fluctuate significantly. You may lose part or all of your investment in the fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks (in alphabetical order) of investing in the fund. An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You may lose money if you invest in this fund.

Active Trading – The fund may purchase and sell securities without regard to the length of time held. Active trading may have a negative impact on performance by increasing transaction costs and may generate greater amounts of net short-term capital gains, which, for shareholders holding shares in taxable accounts, would generally be subject to tax at ordinary income tax rates upon distribution. During periods of market volatility, active trading may be more pronounced.

Currency – The value of investments in securities denominated in foreign currencies increases or decreases as the rates of exchange between those currencies and the U.S. dollar change. Currency conversion costs and currency fluctuations could reduce or eliminate investment gains or add to investment losses. Currency exchange rates can be volatile and may fluctuate significantly over short periods of time, and are affected by factors such as general economic conditions, the actions of the U.S. and foreign governments or central banks, the imposition of currency controls, and speculation.

Cybersecurity – Cybersecurity incidents may allow an unauthorized party to gain access to fund assets, shareholder data (including private shareholder information), and/or proprietary information, or cause the fund, TAM, a sub-adviser and/or the fund's other service providers (including, but not limited to, fund accountants, custodians, sub-custodians, transfer agents and financial intermediaries) to suffer data breaches, data corruption or loss of operational functionality. A cybersecurity incident may disrupt the processing of shareholder transactions, impact the fund's ability to calculate its net asset values, and prevent shareholders from redeeming their shares.

Depositary Receipts – Depositary receipts may be less liquid than the underlying shares in their primary trading market. Any distributions paid to the holders of depositary receipts are usually subject to a fee charged by the depositary. Holders of depositary receipts may have limited voting rights, and investment restrictions in certain countries may adversely impact the value of depositary receipts because such restrictions may limit the ability to convert equity shares into depositary receipts and vice versa. Such restrictions may cause equity shares of the underlying issuer to trade at a discount or premium to the market price of the depositary receipts.

Emerging Markets – Investments in the securities of issuers located in or principally doing business in emerging markets are subject to heightened foreign investments risks. Emerging market countries tend to have economic, political and legal systems and regulatory and accounting standards that are less fully developed, and that can be expected to be less stable. For example, the economies of such countries can be subject to rapid and unpredictable rates of inflation or deflation. Emerging market countries may have policies that restrict investment by foreigners or that prevent foreign investors from withdrawing their money at will. Emerging market securities are often particularly sensitive to market movements because their market prices tend to reflect speculative expectations. Low trading volumes may result in a lack of liquidity and in extreme price volatility. The fund may be required to establish special custody or other arrangements before investing in emerging market countries. An investment in emerging market securities should be considered speculative.

Equity Securities – Equity securities represent an ownership interest in an issuer, rank junior in a company’s capital structure and consequently may entail greater risk of loss than debt securities. Equity securities include common and preferred stocks. Stock markets are volatile and the value of equity securities may go up or down sometimes rapidly and unpredictably. Equity securities may have greater price volatility than other asset classes, such as fixed income securities. The value of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions. If the market prices of the equity securities owned by the fund fall, the value of your investment in the fund will decline. If the fund holds equity securities in a company that becomes insolvent, the fund’s interests in the company will rank junior in priority to the interests of debtholders and general creditors of the company.

Foreign Investments – Investing in securities of foreign issuers or issuers with significant exposure to foreign markets involves additional risk. Foreign countries in which the fund may invest may have markets that are less liquid, less regulated, less transparent and more volatile than U.S. markets. The value of the fund’s investments may decline because of factors affecting the particular issuer as well as foreign markets and issuers generally, such as unfavorable or unsuccessful government actions, reduction of government or central bank support, political or financial instability or other adverse economic or political developments. Lack of information and weaker accounting standards also may affect the value of these securities.

Investments by Affiliated Funds and Unaffiliated Funds – A significant portion of the fund’s shares may be owned by other funds sponsored by Transamerica and/or parties not affiliated with Transamerica. Transactions by these funds may be disruptive to the management of the fund. For example, the fund may experience large redemptions and could be required to sell securities at a time when it may not otherwise desire to do so. Such transactions may increase the fund’s brokerage and/or other transaction costs and could also accelerate the realization of taxable capital gains in the fund. In addition, sizeable redemptions could cause the fund’s total expenses to increase.

Legal and Regulatory – Legal and regulatory changes could occur that may adversely affect the fund, its investments, and its ability to pursue its investment strategies and/or increase the costs of implementing such strategies. New or revised laws or regulations may be imposed by the U.S. Securities and Exchange Commission, the U.S. Commodity Futures Trading Commission, the Internal Revenue Service, the U.S. Federal Reserve or other governmental regulatory authorities or self-regulatory organizations that could adversely affect the fund. The fund also may be adversely affected by changes in the enforcement or interpretation of existing statutes and rules by governmental regulatory authorities or self-regulatory organizations.

Liquidity – The fund may make investments that are illiquid or that become illiquid after purchase. Investments may become illiquid due to the lack of an active market, a reduced number of traditional market participants, or reduced capacity of traditional market participants to make a market in securities. The liquidity and value of investments can deteriorate rapidly and those investments may be difficult or impossible for the fund to sell, particularly during times of market turmoil. Illiquid investments can be difficult to value, may trade at a discount from comparable, more liquid investments, and may be subject to wide fluctuations in value. As a general matter, dealers recently have been less willing to make markets for fixed income securities. If the fund is forced to sell an illiquid investment to meet redemption requests or other cash needs, the fund may be forced to sell at a loss. The fund may not receive its proceeds from the sale of certain securities for an extended period (for example, several weeks or even longer).

Management – The fund is subject to the risk that the investment manager’s or sub-adviser’s judgments and decisions may be incorrect or otherwise may not produce the desired results, causing the value of your investment to go down. The fund may also suffer losses if there are imperfections, errors or limitations in the quantitative, analytic or other tools, resources, information and data used, investment techniques applied, or the analyses employed or relied on, by the investment manager or sub-adviser, if such tools, resources, information or data are used incorrectly or otherwise do not work as intended, or if the investment manager’s or sub-adviser’s investment style is out of favor or otherwise fails to produce the desired results. In addition, the fund’s investment strategies or policies may change from time to time. Those changes may not lead to the results intended by the investment manager or sub-adviser and could have an adverse effect on the value or performance of the fund. Any of these things could cause the fund to lose value or its results to lag relevant benchmarks or other funds with similar objectives.

Market – The value of the fund's securities may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic or political conditions, inflation, changes in interest rates or currency rates, lack of liquidity in the markets or adverse investor sentiment. Adverse market conditions may be prolonged and may not have the same impact on all types of securities. The value of securities also may go down due to events or conditions that affect particular sectors, industries or issuers. If the value of the securities owned by the fund fall, the value of your investment will go down. The fund may experience a substantial or complete loss on any individual security.

In the past decade, financial markets throughout the world have experienced increased volatility, depressed valuations, decreased liquidity and heightened uncertainty. Governmental and non-governmental issuers have defaulted on, or been forced to restructure, their debts. These market conditions may continue, worsen or spread. Events that have contributed to these market conditions include, but are not limited to, major cybersecurity events; geopolitical events (including wars and terror attacks); measures to address budget deficits; downgrading of sovereign debt; declines in oil and commodity prices; dramatic changes in currency exchange rates; and public sentiment. The European Union has experienced increasing stress for a variety of reasons, including economic downturns in various member countries. In June 2016, the United Kingdom voted to withdraw from the European Union, and additional members could do the same. The impact of these conditions and events is not yet known.

There has been significant U.S. and non-U.S. government and central bank intervention in and support of financial markets during the past decade. The Federal Reserve has reduced and begun unwinding its market support activities and has begun raising interest rates. Certain foreign governments and central banks are implementing so-called negative interest rates (e.g., charging depositors who keep their cash at a bank) to spur economic growth. Further Federal Reserve or other U.S. or non-U.S. governmental or central bank actions, including interest rate increases, unwinding of quantitative easing, or contrary actions by different governments, may not work as intended, could negatively affect financial markets generally, increase market volatility, and reduce the value and liquidity of securities in which the fund invests.

Policy and legislative changes in the United States and in other countries are affecting many aspects of financial regulation, and may in some instances contribute to decreased liquidity and increased volatility in the financial markets. The impact of these changes on the markets, and the practical implications for market participants, may not be fully known for some time.

Economies and financial markets throughout the world are increasingly interconnected. Economic, financial or political events, trading and tariff arrangements, terrorism, natural disasters and other circumstances in one country or region could have profound impacts on global economies or markets. As a result, whether or not the fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the fund's investments may be negatively affected.

Small Capitalization Companies – The fund will be exposed to additional risks as a result of its investments in the securities of small capitalization companies. Small capitalization companies may be more at risk than larger capitalization companies because, among other things, they may have limited product lines, operating history, market or financial resources, or because they may depend on limited management groups. The prices of securities of small capitalization companies generally are more volatile than those of larger capitalization companies and are more likely to be adversely affected than larger capitalization companies by changes in earnings results and investor expectations or poor economic or market conditions. Securities of small capitalization companies may underperform larger capitalization companies, may be harder to sell at times and at prices the portfolio managers believe appropriate and may offer greater potential for losses.

Valuation – The sales price the fund could receive for any particular portfolio investment may differ from the fund's valuation of the investment, particularly for securities that trade in thin or volatile markets, that are priced based upon valuations provided by third-party pricing services that use matrix or evaluated pricing systems, or that are valued using a fair value methodology. Investors who purchase or redeem fund shares on days when the fund is holding fair-valued securities may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the fund had not fair-valued securities or had used a different valuation methodology. The fund's ability to value its investments may be impacted by technological issues and/or errors by pricing services or other third party service providers.

Value Investing – The prices of securities the sub-adviser believes are undervalued may not appreciate as anticipated or may go down. The value approach to investing involves the risk that stocks may remain undervalued, undervaluation may become more severe, or perceived undervaluation may actually represent intrinsic value. Value stocks as a group may be out of favor and underperform the overall equity market for a long period of time, for example, while the market favors “growth” stocks.

Risk Lose Money [Text]

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<b>You may lose money if you invest in this fund.</b>

Risk Not Insured Depository Institution [Text]

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An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Bar Chart and Performance Table [Heading]

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<b>Performance:</b>

Performance Narrative [Text Block]

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The bar chart and the table below provide some indication of the risks of investing in the fund. The bar chart shows how the fund’s performance has varied from year to year. The table shows how the fund’s average annual total returns for different periods compare to the returns of a broad measure of market performance.

As with all mutual funds, past performance (before and after taxes) is not a prediction of future results. Updated performance information is available on our website at www.transamerica.com/individual/products/mutual-funds/performance/ or by calling 1-888-233-4339.

Performance Information Illustrates Variability of Returns [Text]

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The bar chart and the table below provide some indication of the risks of investing in the fund. The bar chart shows how the fund’s performance has varied from year to year. The table shows how the fund’s average annual total returns for different periods compare to the returns of a broad measure of market performance.

Performance Availability Phone [Text]

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1-888-233-4339

Performance Availability Website Address [Text]

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www.transamerica.com/individual/products/mutual-funds/performance/

Performance Past Does Not Indicate Future [Text]

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As with all mutual funds, past performance (before and after taxes) is not a prediction of future results.

Bar Chart [Heading]

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<b>Annual Total Returns (calendar years ended December 31) - Class I</b>

Bar Chart Closing [Text Block]

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	Quarter Ended	Return
Best Quarter:	06/30/2017	7.65%
Worst Quarter:	12/31/2018	-14.74%

Performance Table Heading

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<b>Average Annual Total Returns (periods ended December 31, 2018)</b>

Performance Table Uses Highest Federal Rate

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The after-tax returns are calculated using the historic 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

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Actual after-tax returns may depend on the investor’s individual tax situation and may differ from those shown. After-tax returns may not be relevant if the investment is made through a tax-exempt or tax-deferred account, such as a 401(k) plan.

Performance Table Narrative

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The after-tax returns are calculated using the historic highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns may depend on the investor’s individual tax situation and may differ from those shown. After-tax returns may not be relevant if the investment is made through a tax-exempt or tax-deferred account, such as a 401(k) plan.

Class I | Transamerica International Small Cap Value | I

Risk/Return:

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Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

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none

Maximum deferred sales charge (load) (as a percentage of purchase price or redemption proceeds, whichever is lower)

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none

Management fees

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0.93%

Distribution and service (12b-1) fees

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none

Other expenses

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0.19%

Total annual fund operating expenses

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1.12%

1 year

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$ 114

3 years

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356

5 years

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617

10 years

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$ 1,363

2014

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(6.28%)

2015

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7.95%

2016

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(0.85%)

2017

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30.47%

2018

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(16.26%)

Highest Quarterly Return, Label

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Best Quarter:

Highest Quarterly Return, Date

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Jun. 30, 2017

Highest Quarterly Return

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7.65%

Lowest Quarterly Return, Label

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Worst Quarter:

Lowest Quarterly Return, Date

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Dec. 31, 2018

Lowest Quarterly Return

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(14.74%)

1 Year

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(16.26%)

5 Years

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1.85%

Since Inception

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5.56%

Inception Date

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Jan. 04, 2013

Class I | Transamerica International Small Cap Value | Return after taxes on distributions | I

Risk/Return:

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1 Year

rr_AverageAnnualReturnYear01

(17.60%)

5 Years

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0.86%

Since Inception

rr_AverageAnnualReturnSinceInception

4.59%

Inception Date

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Jan. 04, 2013

Class I | Transamerica International Small Cap Value | Return after taxes on distributions and sale of fund shares | I

Risk/Return:

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1 Year

rr_AverageAnnualReturnYear01

(8.33%)

5 Years

rr_AverageAnnualReturnYear05

1.46%

Since Inception

rr_AverageAnnualReturnSinceInception

4.36%

Inception Date

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Jan. 04, 2013

Class I | Transamerica International Small Cap Value | MSCI EAFE Small Cap Index Gross (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(17.58%)

5 Years

rr_AverageAnnualReturnYear05

3.42%

Since Inception

rr_AverageAnnualReturnSinceInception

7.12%