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 High Yield Bond

Risk/Return:

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Risk/Return [Heading]

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TRANSAMERICA HIGH YIELD BOND

Objective [Heading]

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Investment Objective:

Objective, Primary [Text Block]

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Seeks a high level of current income by investing in high-yield debt securities.

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 48% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

48.00%

Expenses Restated to Reflect Current [Text]

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Management fees have been restated to reflect a reduction in advisory fees effective May 1, 2014.

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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The fund’s sub-adviser, Aegon USA Investment Management, LLC (the “sub-adviser”), seeks to achieve the fund’s objective by investing, under normal circumstances, at least 80% of the fund’s net assets (plus the amount of borrowings, if any, for investment purposes) in high-yield/high-risk bonds (commonly known as “junk bonds”).

Junk bonds are high risk debt securities rated below investment grade or determined by the sub-adviser to be of comparable quality. The sub-adviser’s strategy is to seek to achieve yields as high as possible while seeking to manage risk. The sub-adviser uses a “top-down/bottom-up” approach in managing the fund’s assets. The “top-down” approach is to adjust the risk profile of the fund. The sub-adviser analyzes four factors that affect the movement of the fixed-income bond prices which include: economic indicators; technical indicators that are specific to the high-yield market; investor sentiment; and valuation. Analysis of these factors assists the sub-adviser in its decision regarding the fund’s portfolio allocations. In a “top-down” approach, the sub-adviser looks at broad market factors and chooses certain sectors or industries within the market, based on those factors. It then looks at individual companies within those sectors or industries.

The sub-adviser has developed a proprietary credit model that is the foundation of its “bottom-up” analysis. The model tracks historical cash flow numbers and calculates credit financial ratios. Because high-yield companies are of higher financial risk, the sub-adviser does a thorough credit analysis of all companies in the fund’s portfolio, as well as all potential acquisitions. A “bottom-up” approach is looking at individual companies against the context of broader market factors.

The fund may invest in loans of foreign-domiciled borrowers and foreign debt securities, including emerging market debt securities, but expects that the majority of assets in which it invests will be invested in loans and securities of U.S. borrowers or issuers. The sub-adviser may sell fund securities when it determines there are changes in economic indicators, technical indicators or valuation.

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.

• Counterparty – The fund will be subject to credit risk (that is, where changes in an issuer’s financial strength or credit rating may affect an instrument’s value) with respect to the amount it expects to receive from counterparties to derivatives, repurchase agreements and other financial contracts entered into by the fund or held by special purpose or structured vehicles. If a counterparty becomes bankrupt or otherwise fails to perform its obligations due to financial difficulties, the value of your investment in the fund may decline.

• Credit – If an issuer or other obligor (such as a party providing insurance or other credit enhancement) of a security held by the fund or a counterparty to a financial contract with the fund defaults or is downgraded, or is perceived to be less creditworthy, or if the value of any underlying assets declines, the value of your investment will typically decline. Below investment grade, high-yield debt securities (commonly known as “junk bonds”) have a higher risk of default and are considered speculative. Subordinated securities are more likely to suffer a credit loss than non-subordinated securities of the same issuer and will be disproportionately affected by a default, downgrade or perceived decline in creditworthiness.

• 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.

• Emerging Markets – Investments in the securities of issuers located in or principally doing business in emerging markets are subject to foreign investments risks. These risks are greater for investments in issuers in emerging market countries. Emerging market countries tend to have economic, political and legal systems that are less fully developed and are less stable than those of more developed countries. 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.

• Extension – When interest rates rise, repayments of fixed income securities, particularly asset- and mortgage-backed securities, may occur more slowly than anticipated, extending the effective duration of these fixed income securities at below market interest rates and causing their market prices to decline more than they would have declined due to the rise in interest rates alone. This may cause the fund’s share price to be more volatile.

• Fixed-Income Securities – The market prices of fixed-income securities may go up or down, sometimes rapidly and unpredictably, due to general market conditions, such as real or perceived adverse economic or political conditions, inflation, changes in interest rates, lack of liquidity in the bond markets or adverse investor sentiment. In addition, the market value of a fixed income security may decline if the issuer or other obligor of the security fails to pay principal and/or interest, otherwise defaults or has its credit rating downgraded or is perceived to be less creditworthy, or the credit quality or value of any underlying assets declines. When market prices fall, the value of your investment will go down. The value of your investment will generally go down when interest rates rise. Interest rates have been at historically low levels, so the fund faces a heightened risk that interest rates may rise. A rise in rates tends to have a greater impact on the prices of longer term or duration securities.

• 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.

• High-Yield Debt Securities – High-yield debt securities, commonly referred to as “junk bonds,” are securities that are rated below “investment grade” (that is, securities rated below Baa/BBB) or, if unrated, determined to be below investment grade by the sub-adviser. Changes in interest rates, the market’s perception of the issuers and the creditworthiness of the issuers may significantly affect the value of these bonds. Junk bonds are considered speculative, have a higher risk of default, tend to be less liquid and may be more difficult to value than higher grade securities. Junk bonds tend to be volatile and more susceptible to adverse events and negative sentiments.

• Interest Rate – Interest rates in the U.S. have been at historically low levels, so the fund faces a heightened risk that interest rates may rise. The value of fixed income securities generally goes down when interest rates rise, and therefore the value of your investment in the fund may also go down. Debt securities have varying levels of sensitivity to changes in interest rates. A rise in rates tends to have a greater impact on the prices of longer term or duration securities.

• Liquidity – The fund may make investments that are illiquid or that become illiquid after purchase. The liquidity and value of investments can deteriorate rapidly and those investments may be difficult or impossible to sell, particularly during times of market turmoil. These illiquid investments may also be difficult to value. 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.

• Loans – Loans are subject to the credit risk of nonpayment of principal or interest. Economic downturns or increases in interest rates may cause an increase in defaults, interest rate risk and liquidity risk. Loans may or may not be collateralized at the time of acquisition, and any collateral may be relatively illiquid or lose all or substantially all of its value subsequent to investment. In the event of bankruptcy of a borrower, the fund could experience delays or limitations with respect to its ability to realize the benefits of any collateral securing a loan. Junior loans, which have a lower place in the borrower’s capital structure than senior loans and may be unsecured, involve a higher degree of overall risk than senior loans of the same borrower. The fund's investments in loans are also subject to prepayment or call risk.

• 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.

• Prepayment or Call – Many issuers have a right to prepay their securities. If interest rates fall, an issuer may exercise this right. If this happens, the fund will not benefit from the rise in market price that normally accompanies a decline in interest rates, and will be forced to reinvest prepayment proceeds at a time when yields on securities available in the market are lower than the yield on the prepaid security. The fund also may lose any premium it paid on the security.

• 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 for 10 years.

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:	06/30/2009	22.95%
Worst Quarter:	12/31/2008	-16.73%

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 High Yield Bond | I2

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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0.55%

^[1]

Distribution and service (12b-1) fees

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none

Other expenses

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0.09%

Total annual fund operating expenses

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0.64%

1 year

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65

3 years

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205

5 years

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357

10 years

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798

2005

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3.24%

2006

rr_AnnualReturn2006

10.73%

2007

rr_AnnualReturn2007

2.06%

2008

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(24.98%)

2009

rr_AnnualReturn2009

57.25%

2010

rr_AnnualReturn2010

13.35%

2011

rr_AnnualReturn2011

4.54%

2012

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17.42%

2013

rr_AnnualReturn2013

6.54%

2014

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3.87%

Highest Quarterly Return, Label

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Best Quarter:

Highest Quarterly Return, Date

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Jun. 30, 2009

Highest Quarterly Return

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22.95%

Lowest Quarterly Return, Label

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Worst Quarter:

Lowest Quarterly Return, Date

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Dec. 31, 2008

Lowest Quarterly Return

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(16.73%)

1 Year

rr_AverageAnnualReturnYear01

3.87%

5 Years

rr_AverageAnnualReturnYear05

9.02%

10 Years

rr_AverageAnnualReturnYear10

7.80%

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 08, 2004

Class I2 | Transamerica High Yield Bond | Return after taxes on distributions | I2

Risk/Return:

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1 Year

rr_AverageAnnualReturnYear01

1.11%

5 Years

rr_AverageAnnualReturnYear05

6.21%

10 Years

rr_AverageAnnualReturnYear10

4.94%

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 08, 2004

Class I2 | Transamerica High Yield Bond | Return after taxes on distributions and sale of fund shares | I2

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

2.37%

5 Years

rr_AverageAnnualReturnYear05

5.89%

10 Years

rr_AverageAnnualReturnYear10

4.88%

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 08, 2004

Class I2 | Transamerica High Yield Bond | Barclays U.S. Corporate High Yield 2% Issuer Capped Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

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1 Year

rr_AverageAnnualReturnYear01

2.46%

5 Years

rr_AverageAnnualReturnYear05

8.98%

10 Years

rr_AverageAnnualReturnYear10

7.73%

[1] Management fees have been restated to reflect a reduction in advisory fees effective May 1, 2014.