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, 2015

Class I2 | Transamerica Small Cap Growth

Risk/Return:

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Risk/Return [Heading]

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TRANSAMERICA SMALL CAP GROWTH

Objective [Heading]

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Investment Objective:

Objective, Primary [Text Block]

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Seeks long-term capital appreciation.

Expense [Heading]

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Fees and Expenses:

Expense Narrative [Text Block]

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

Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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

Portfolio Turnover [Heading]

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Portfolio Turnover:

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 73% of the average value of its portfolio.

Portfolio Turnover, Rate

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73.00%

Expense Example [Heading]

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Example:

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. 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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Principal Investment Strategies:

Strategy Narrative [Text Block]

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Under normal circumstances, the fund invests at least 80% of its net assets (plus the amount of borrowing, if any, for investment purposes) in stocks of small capitalization companies. The fund’s sub-adviser, Ranger Investment Management, L.P. (the “sub-adviser”), primarily focuses on seeking to identify high quality, high-growth small capitalization companies. The sub-adviser considers small capitalization companies to be companies with market capitalizations that, at the time of initial purchase, have either market capitalizations between $100 million and $2 billion or within the range of the Russell 2000^® Growth Index¹, which as of June 30, 2014, the most recent reconstitution date of the index, was between $143 million and $4.5 billion.

The sub-adviser’s approach to security selection seeks quality growth companies by implementing a bottom-up, fundamental research driven security selection process. The sub-adviser’s focus is to attempt to identify companies with characteristics such as high recurring revenue, steady and/or accelerating sales growth, strong balance sheets and free cash flows, stable/expanding margins, and superior return on equity/return on invested capital. In addition to the extensive quantitative analysis, careful consideration is given to qualitative analysis. The sub-adviser incorporates a preference towards companies with certain qualitative characteristics such as conservative accounting practices, seasoned management team with high corporate integrity, sustainable competitive advantage and ability to grow market share, sound corporate governance, and unique demand drivers. Once these quantitative and qualitative characteristics are analyzed, the sub-adviser then determines whether it believes a company is undervalued and has sufficient upside to the stock price to warrant an investment.

The fund may invest in foreign securities through American Depositary Receipts (“ADRs”), and generally will not invest more than 10% of fund assets in foreign securities. The fund only invests in securities traded on U.S. exchanges.

¹ Russell Investment Group is the source and owner of the trademarks, service marks and copyrights related to the Russell indexes. Russell^® is a trademark of Russell Investment Group.

Risk [Heading]

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Principal Risks:

Risk Narrative [Text Block]

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Risk is inherent in all investing. Many factors affect the fund's performance. There is no assurance the fund will meet its investment objective. 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 fund may take temporary defensive positions; in such a case, the fund will not be pursuing its principal investment strategies. The following is a summary description of principal risks (in alphabetical order) of investing in the fund. You may lose money if you invest in this fund.

• Active Trading – The fund is actively managed and 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 be subject to tax at ordinary income tax rates upon distribution.

• 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 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.

• 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.

• 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. The price 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.

• Focused Investing – To the extent the fund invests in one or more countries, regions, sectors or industries, or in a limited number of issuers, the fund will be more susceptible to negative events affecting those countries, regions, sectors, industries or issuers. Local events, such as political upheaval, financial troubles, or natural disasters may disrupt a country’s or region’s securities markets. Geographic risk is especially high in emerging markets.

• 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 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 government actions, 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.

• Growth Stocks – Returns on growth stocks may not move in tandem with returns on other categories of stocks or the market as a whole. Growth stocks may be particularly susceptible to larger price swings or to adverse developments. Growth 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 “value” stocks.

• Manager – The fund is subject to the risk that the sub-adviser’s judgments and investment decisions, as well as the methods, tools, resources, information and data, and the analyses employed or relied on by the sub-adviser to make those judgments and decisions may be incorrect or otherwise may not produce the desired results. This could cause the fund to lose value or its results to lag relevant benchmarks or other funds with similar objectives.

• Market – The market prices 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. Market prices of securities also may go down due to events or conditions that affect particular sectors, industries or issuers. When market prices fall, the value of your investment will go down. The fund may experience a substantial or complete loss on any individual security. Financial markets in the U.S., Europe and elsewhere have experienced increased volatility and decreased liquidity since the global financial crisis began in 2008. Governmental and non-governmental issuers defaulted on, or were forced to restructure, their debts. These market conditions may continue, worsen or spread. The U.S. government and the Federal Reserve, as well as certain foreign governments and their central banks have taken steps to support financial markets, including keeping interest rates at historically low levels. More recently, the Federal Reserve has reduced its market support activities. Further reduction or withdrawal of this support, or other related efforts in response to the crisis could negatively affect financial markets generally and increase market volatility as well as result in higher interest rates and reduce the value and liquidity of certain securities. This environment could make identifying investment risks and opportunities especially difficult for the sub-adviser. Whether or not the fund invests in securities of issuers located in or with significant exposure to countries experiencing economic and financial difficulties, the value and liquidity of the fund's investments may be negatively affected. In addition, policy and legislative changes in the United States and in other countries are affecting many aspects of financial regulation, and in some instances may contribute to decreased liquidity and increased volatility in the financial markets.

• Portfolio Selection – The value of your investment may decrease if the sub-adviser’s judgment about the quality, relative yield, value or market trends affecting a particular security or issuer, industry, sector, region or market segment, or about the economy or interest rates is incorrect.

• 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.

Risk Lose Money [Text]

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You may lose money if you invest in this fund.

Bar Chart and Performance Table [Heading]

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Performance:

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. Absent any limitation of the fund’s expenses, total returns would be lower. Index returns are since the inception of the oldest share class.

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/index.html 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/index.html

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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Annual Total Returns (calendar years ended December 31) - Class I2

Bar Chart Closing [Text Block]

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	Quarter Ended	Return
Best Quarter:	09/30/2013	12.37%
Worst Quarter:	09/30/2014	-4.56%

Performance Table Heading

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Average Annual Total Returns (periods ended December 31, 2014)

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 I2 | Transamerica Small Cap Growth | I2

Risk/Return:

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

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

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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0.82%

Distribution and service (12b-1) fees

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none

Other expenses

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0.07%

Total annual fund operating expenses

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0.89%

1 year

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91

3 years

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284

5 years

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493

10 years

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1,096

2013

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37.33%

2014

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3.20%

Highest Quarterly Return, Label

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Best Quarter:

Highest Quarterly Return, Date

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Sep. 30, 2013

Highest Quarterly Return

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12.37%

Lowest Quarterly Return, Label

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Worst Quarter:

Lowest Quarterly Return, Date

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Sep. 30, 2014

Lowest Quarterly Return

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(4.56%)

1 Year

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3.20%

Since Inception

rr_AverageAnnualReturnSinceInception

12.86%

Inception Date

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Aug. 31, 2012

Class I2 | Transamerica Small Cap Growth | Return after taxes on distributions | I2

Risk/Return:

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1 Year

rr_AverageAnnualReturnYear01

1.25%

Since Inception

rr_AverageAnnualReturnSinceInception

11.93%

Inception Date

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Aug. 31, 2012

Class I2 | Transamerica Small Cap Growth | Return after taxes on distributions and sale of fund shares | I2

Risk/Return:

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1 Year

rr_AverageAnnualReturnYear01

3.40%

Since Inception

rr_AverageAnnualReturnSinceInception

9.97%

Inception Date

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Aug. 31, 2012

Class I2 | Transamerica Small Cap Growth | Russell 2000® Growth Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

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1 Year

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5.60%

Since Inception

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21.39%