Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	TRANSAMERICA FUNDS
Prospectus Date	rr_ProspectusDate	Mar. 01, 2022
Class I2 | Transamerica Multi-Asset Income
Risk Return Abstract	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	<span style="color:#000000;font-family:Times New Roman;font-size:11pt;font-weight:bold;">Transamerica Multi-Asset Income</span>
Objective [Heading]	rr_ObjectiveHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Investment Objective:</span>
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Seeks current income while providing long-term capital appreciation.
Expense [Heading]	rr_ExpenseHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Fees and Expenses:</span>
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	<span style="color:#000000;font-family:Times New Roman;font-size:9pt;font-weight:bold;margin-left:0%;">Shareholder Fees (fees paid directly from your investment)</span>
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	<span style="color:#000000;font-family:Times New Roman;font-size:9pt;font-weight:bold;">Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)</span>
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Portfolio Turnover:</span>
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 portfolio turnover rate for the fund was 45% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	45.00%
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]	rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees	<span style="font-family:Times New Roman;font-size:8pt;"> Acquired fund fees and expenses are not included in the calculation of the ratios of expenses to average net assets shown in the Financial Highlights section of the fund’s prospectus.</span>
Expense Example [Heading]	rr_ExpenseExampleHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Example:</span>
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	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]	rr_StrategyHeading	<span style="font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Principal Investment Strategies:</span>
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The fund’s sub-adviser, Thompson, Siegel & Walmsley LLC (the “sub-adviser”), deploys an active strategy that normally seeks to invest in a range of securities, including primarily U.S. stocks with market capitalizations at the time of purchase in excess of $3 billion, preferred stocks, and income producing fixed-income securities. Under normal market conditions, the fund invests in a diversified portfolio of credit and equity securities and may shift its investments from one asset class to another in seeking to achieve the fund’s income objective.The sub-adviser employs a strategic approach to asset allocation and uses a “bottom-up” fundamental investment approach to security selection. The sub-adviser expects to generally invest the fund’s portfolio in a mix of common stock, preferred stock and fixed-income securities, normally targeting allocations of 40%, 20% and 40%, respectively for these security types. Depending on market factors, these allocations may range from approximately 20% to 60% for common stock, 0% to 40% for preferred stock and 20% to 60% for fixed-income securities.The equity securities in which the fund invests typically consist primarily of common stocks. Debt securities in which the fund invests normally include primarily high yield bonds (also known as “junk bonds”), although the fund may hold other fixed-income securities including various fixed, floating and variable rate instruments, secured and unsecured bonds, bonds convertible into common stock, senior floating rate and term loans, debentures, shorter term instruments and closed-end funds. The fund may invest all of its fixed-income allocation in securities that are rated below investment grade.The fund may invest in fixed-income securities of any maturity and does not have a target average duration. The fund maintains the flexibility to invest in securities of companies from a variety of sectors, but from time to time, based on economic conditions, the fund may have significant investments in one or more particular sectors. The fund may also invest up to 25% of its assets in foreign securities, either directly or through depositary receipts. The fund may also invest in exchange-traded funds (“ETFs”).
Risk [Heading]	rr_RiskHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Principal Risks:</span>
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Risk is inherent in all investing. Many factors and risks affect the fund's performance, including those described below. The value of your investment in the fund, as well as the amount of return you receive on your investment, may fluctuate significantly day to day and over time. 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 after certain key risks) 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.Market – The market prices of the fund’s securities or other assets may go up or down, sometimes rapidly or unpredictably, due to general market conditions, overall economic trends or events, inflation, changes in interest rates, governmental actions or interventions, actions taken by the U.S. Federal Reserve or foreign central banks, market disruptions caused by tariffs, trade disputes or other factors, political developments, investor sentiment, the global and domestic effects of a pandemic, and other factors that may or may not be related to the issuer of the security or other asset. If the market prices of the fund’s securities and assets fall, the value of your investment will go down.Economies and financial markets throughout the world are increasingly interconnected. Economic, financial or political events, trading and tariff arrangements, public health events (such as the spread of infectious disease), wars, terrorism, cybersecurity events,technology and data interruptions, natural disasters, and other circumstances in one or more countries or regions could be highly disruptive to, and 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 go down.The pandemic of the novel coronavirus respiratory disease designated COVID-19 has resulted in extreme volatility in the financial markets, a domestic and global economic downturn, severe losses, particularly to some sectors of the economy and individual issuers, and reduced liquidity of many instruments.There also have been significant disruptions to business operations, including business closures; strained healthcare systems; disruptions to supply chains and employee availability; large fluctuations in consumer demand; and widespread uncertainty regarding the duration and long-term effects of the pandemic. The domestic and global economic downturn may be prolonged. The pandemic may result in domestic and foreign political and social instability, damage to diplomatic and international trade relations, and continued volatility and/or decreased liquidity in the securities markets. Developing or emerging market countries may be more impactedby the pandemic.The U.S. government and the Federal Reserve, as well as certain foreign governments and central banks, have taken extraordinary actions to support local and global economies and the financial markets in response to the COVID-19 pandemic, including by pushing interest rates to very low levels. This and other government intervention into the economy and financial markets to address the pandemic may not work as intended, particularly if the efforts are perceived by investors as being unlikely to achieve the desired results. Government actions to mitigate the economic impact of the pandemic have resulted in large expansion of government deficits and debt, the long-term consequences of which are not known. Rates of inflation have recently risen, which could adversely affect economies and markets.The COVID-19 pandemic could continue to adversely affect the value and liquidity of the fund’s investments, impair the fund’s ability to satisfy redemption requests, and negatively impact the fund’s performance. In addition, the pandemic, and measures taken to mitigate its effects, could result in disruptions to the services provided to the fund by its service providers.Asset Allocation – The fund’s investment performance is significantly impacted by the fund’s asset allocation and reallocation from time to time. The sub-adviser's decisions whether and when to tactically overweight or underweight asset classes, create and apply formulas for de-risking or ending de-risking may not produce the desired results. These actions may be unsuccessful in maximizing return and/or avoiding investment losses. The value of your investment may decrease if the sub-adviser’s judgment about the attractiveness, value or market trends affecting a particular asset class, investment style, technique or strategy or other issuer is incorrect. The sub-adviser may favor an asset class that performs poorly relative to other asset classes.Equity Securities – Equity securities generally have greater risk of loss than debt securities. Stock markets are volatile and the value of equity securities may go up or down, sometimes rapidly and unpredictably. The value of equity securities fluctuates based on real or perceived changes in a company’s financial condition, factors affecting a particular industry or industries, and overall market, economic and political conditions. If the market prices of the equity securities owned by the fund fall, the value of your investment in the fund will decline. The fund may lose its entire investment in the equity securities of an issuer. A change in financial condition or other event affecting a single issuer may adversely impact securities markets as a whole.Interest Rate – Interest rates in the U.S. and certain foreign markets have been low relative to historic levels. The fund faces a risk that interest rates may rise. The value of fixed-income securities generally goes down when interest rates rise. A rise in rates tends to have a greater impact on the prices of longer term or duration securities. Changes in interest rates also may affect the liquidity of the fund’s investments. A general rise in interest rates may cause investors to sell fixed-income securities on a large scale, which could adversely affect the price and liquidity of fixed-income securities generally and could also result in increased redemptions from the fund. Increased redemptions could cause the fund to sell securities at inopportune times or depressed prices and result in further losses.High-Yield Debt Securities – High-yield debt securities, commonly referred to as “junk” bonds, are securities that are rated below “investment grade” or are of comparable quality. Changes in interest rates, the market’s perception of the issuers, the creditworthiness of the issuers and negative perceptions of the junk bond market generally may significantly affect the value of these bonds. Junk bonds are considered speculative, tend to be volatile, typically have a higher risk of default, tend to be less liquid and more difficult to value than higher grade securities, and may result in losses for the fund.Preferred Stock – Preferred stock’s right to dividends and liquidation proceeds is junior to the rights of a company’s debt securities. The value of preferred stock may be subject to factors that affect fixed-income and equity securities. The value of preferred stock tends to vary more with fluctuations in the underlying common stock and less with fluctuations in interest rates and tends to exhibit greater volatility.Fixed-Income Securities – Risks of fixed-income securities include credit risk, interest rate risk, counterparty risk, prepayment risk, extension risk, valuation risk, and liquidity risk. The value 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, tariffs and trade disruptions, inflation, changes in interest rates, lack of liquidity in the bond markets or adverse investor sentiment. In addition, the 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. If the value of fixed-income securities owned by the fund falls, the value of your investment will go down. The fund may lose its entire investment in the fixed-income securities of an issuer.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 is unable or unwilling to meet its financial obligations, or is downgraded or perceived to be less creditworthy (whether by market participants or otherwise), or if the value of any underlying assets declines, the value of your investment will typically decline. A decline may be significant, particularly in certain market environments. In addition, the fund may incur costs and may be hindered or delayed in enforcing its rights against an issuer, obligor or counterparty.Liquidity – The fund may make investments that are illiquid or that become illiquid after purchase. 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. 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 substantial loss or may not be able to sell at all. Liquidity of particular investments, or even entire asset classes, including U.S. Treasury securities, can deteriorate rapidly, particularly during times of market turmoil, and those investments may be difficult or impossible for the fund to sell. This may prevent the fund from limiting losses.Counterparty – The fund could lose money if the counterparties to derivatives, repurchase agreements and other financial contracts entered into for the fund do not fulfill their contractual obligations. In addition, the fund may incur costs and may be hindered or delayed in enforcing its rights against a counterparty.Extension – When interest rates rise, repayments of fixed-income securities, including asset- and mortgage-backed securities, may occur more slowly than anticipated, causing their market prices to decline.Prepayment or Call – Many issuers have a right to prepay their fixed-income securities. If this happens, the fund will not benefit from the rise in the market price of the securities that normally accompanies a decline in interest rates and may be forced to reinvest the prepayment proceeds in securities with lower yields.Management – The value of your investment may go down if the investment manager’s or sub-adviser's judgments and decisions are incorrect or otherwise do not produce the desired results, or if the investment strategy does not work as intended. You 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. Any of these things could cause the fund to lose value or its results to lag relevant benchmarks or other funds with similar objectives.Active Trading – The fund may purchase and sell securities without regard to the length of time held. Active trading may be more pronounced during periods of market volatility, may have a negative impact on performance and may generate greater amounts of short-term capital gains.Convertible Securities – Convertible securities are subject to risks associated with both fixed-income and equity securities. For example, if market interest rates rise, the value of a convertible security typically falls. In addition, a convertible security is subject to the risk that the issuer will not be able to pay interest or dividends when due, and the market value of the security may change based on the issuer’s actual or perceived creditworthiness. Since the convertible security derives a portion of its value from the underlying common stock, the security is also subject to the same types of market and issuer-specific risks that apply to the underlying common stock. Convertible securities generally offer lower interest or dividend yields than non-convertible securities of similar quality.Currency – The value of a fund’s investments in securities denominated in foreign currencies increases or decreases as the rates of exchange between those currencies and the U.S. dollar change. U.S. dollar-denominated securities of foreign issuers may also be affected by currency risk. Currency exchange rates can be volatile and may fluctuate significantly over short periods of time. Currency conversion costs and currency fluctuations could reduce or eliminate investment gains or add to investment losses. A fund may be unable or may choose not to hedge its foreign currency exposure.Depositary Receipts – Depositary receipts are generally subject to the same risks as are the foreign securities that they evidence or into which they may be converted, and they may be less liquid than the underlying shares in their primary trading market. 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.Foreign Investments – Investing in securities of foreign issuers or issuers with significant exposure to foreign markets involves additional risks. Foreign markets can be less liquid, less regulated, less transparent and more volatile than U.S. markets. The value of the fund’s foreign investments may decline, sometimes rapidly or unpredictably, 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, tariffs and trade disruptions, sanctions, political or financial instability, social unrest or other adverse economic or political developments. Foreign investments may also be subject to different accounting practices and different regulatory, legal, auditing, financial reporting and recordkeeping standards and practices, and may be more difficult to value than investments in U.S. issuers.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 typically are particularly sensitive to market movements and may involve larger price swings because their market prices tend to reflect future expectations. When it appears those expectations may not be met, the prices of growth securities typically fall. 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.Inflation – The value of assets or income from investment may be worth less in the future as inflation decreases the value of money. As inflation increases, the real value of the fund’s assets can decline as can the value of the fund’s distributions.Investment Companies – To the extent that the fund invests in other investment companies, such as open-end funds, closed-end funds or exchange-traded funds, it is subject to the risks of those investment companies and bears its pro rata share of the other investment companies’ expenses.Large Capitalization Companies – The fund’s investments in larger, more established companies may underperform other segments of the market because they may be less responsive to competitive challenges and opportunities and unable to attain high growth rates during periods of economic expansion.Large Shareholder – A significant portion of the fund’s shares may be owned by other funds sponsored by 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. These transactions may also accelerate the realization of taxable income to shareholders if such sales of investments resulted in gains. In addition, sizeable redemptions could cause the fund’s total expenses to increase.LIBOR – Many financial instruments, financings or other transactions to which the fund may be a party use or may use a floating rate based on the London Interbank Offered Rate (“LIBOR”). The UK Financial Conduct Authority and LIBOR’s administrator announced that the use of LIBOR will be phased out; most LIBOR rates are no longer published as of the end of 2021 and a majority of U.S. dollar LIBOR rates will no longer be published after June 30, 2023. It is possible that a subset of LIBOR rates may be published after these dates on a “synthetic” basis, but any such publications would be considered non-representative of the underlying market. There remains uncertainty regarding the nature of any replacement rate and the impact of the transition from LIBOR on the fund, issuers of instruments in which the fund invests, and financial markets generally. As such, the potential effect of a transition away from LIBOR on the fund or the fund’s investments cannot yet be determined.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. The fund's investments in loans are also subject to prepayment or call risk.Medium Capitalization Companies – The fund will be exposed to additional risks as a result of its investments in the securities of medium capitalization companies. Investing in medium capitalization companies involves greater risk than is customarily associated with more established companies. The prices of securities of medium capitalization companies generally are more volatile and are more likely to be adversely affected by changes in earnings results and investor expectations or poor economic or market conditions. Securities of medium 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.Privately Placed and Other Restricted Securities – Restricted securities, which include private placements of private and public companies, are subject to legal or contractual restrictions on their resale. Restricted securities may be difficult to sell at the time and price a fund prefers. Restricted securities may be difficult to value properly and may involve greater risks than securities that are not subject to restrictions on resale, both of which may result in substantial losses. An insufficient number of eligible buyers interested in purchasing restricted securities held by a fund could adversely affect the marketability of such securities and a fund might be unable to dispose of such securities promptly or at reasonable prices, adversely affecting a fund’s overall liquidity and performance. Restricted securities may not be listed on an exchange and may have no active trading market. A fund may incur additional expense when disposing of restricted securities. Restricted securities may involve a high degree of business and financial risk and may result in substantial losses to the fund.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. Securities of small capitalization companies are generally more volatile than and 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.Underlying Exchange-Traded Funds – To the extent the fund invests its assets in underlying ETFs, its ability to achieve its investment objective will depend in part on the performance of the underlying ETFs in which it invests. Investing in underlying ETFs subjects the fund to the risks of investing in the underlying securities or assets held by those ETFs. Each of the underlying ETFs in which the fund may invest has its own investment risks, and those risks can affect the value of the underlying ETFs’ shares and therefore the value of the fund's investments. There can be no assurance that the investment objective of any underlying ETF will be achieved. In addition, the fund will bear a pro rata portion of the operating expenses of the underlying ETFs in which it invests.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. These differences may increase significantly and affect fund investments more broadly during periods of market volatility. 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 also 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]	rr_RiskLoseMoney	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">You may lose money if you invest in this fund.</span>
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;">An investment in the fund is </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span>
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0%;">Performance:</span>
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	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 well as comparison to one or more secondary indices.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/investments-fund-center or by calling 1-888-233-4339.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;"> 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 well as comparison to one or more secondary indices.</span>
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	<span style="font-family:Times New Roman;font-size:10pt;">1-888-233-4339</span>
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	<span style="font-family:Times New Roman;font-size:10pt;">www.transamerica.com/investments</span><span style="font-family:Times New Roman;font-size:10pt;">-fund-center</span>
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	<span style="font-family:Times New Roman;font-size:10pt;margin-left:0%;">As with all mutual funds, past performance (before and after taxes) </span><span style="font-family:Times New Roman;font-size:10pt;">is not a prediction of future results.</span>
Bar Chart [Heading]	rr_BarChartHeading	<span style="font-family:Times New Roman;font-size:8.5pt;font-weight:bold;margin-left:0%;">Annual Total Returns (calendar years ended December 31) - Class I2</span>
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Quarter EndedReturnBest Quarter:6/30/202015.52%Worst Quarter:3/31/2020-18.16%
Performance Table Heading	rr_PerformanceTableHeading	<span style="font-family:Times New Roman;font-size:8.5pt;font-weight:bold;margin-left:0%;">Average Annual Total Returns (periods ended December 31, </span><span style="font-family:Times New Roman;font-size:8.5pt;font-weight:bold;line-height:11pt;"> </span><span style="font-family:Times New Roman;font-size:8.5pt;font-weight:bold;">2021)</span>
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;margin-left:0%;">The after-tax returns are calculated using the historic highest individual</span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;"> federal marginal income tax rates and do not reflect the impact of state and local taxes.</span>
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	<span style="color:#000000;font-family:Times New Roman;font-size:10pt;"> Actual after-tax returns may depend on the investor’s individual tax situation and may differ from those </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;margin-left:0%;">shown. After-tax returns may not be relevant if the investment is </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">made through a tax-exempt or tax-deferred account, such as a 401(k) plan.</span>
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	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 Multi-Asset Income | I2
Risk Return Abstract	rr_RiskReturnAbstract
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)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.57%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.07%
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.03%	[1],[2]
Total annual fund operating expenses	rr_ExpensesOverAssets	0.67%
Fee waiver and/or expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	0.03%	[2]
Total annual fund operating expenses after fee waiver and/or expense reimbursement	rr_NetExpensesOverAssets	0.64%
1 year	rr_ExpenseExampleYear01	$ 65
3 years	rr_ExpenseExampleYear03	211
5 years	rr_ExpenseExampleYear05	370
10 years	rr_ExpenseExampleYear10	$ 832
2015	rr_AnnualReturn2015	(3.07%)
2016	rr_AnnualReturn2016	6.62%
2017	rr_AnnualReturn2017	13.65%
2018	rr_AnnualReturn2018	(3.43%)
2019	rr_AnnualReturn2019	20.57%
2020	rr_AnnualReturn2020	11.61%
2021	rr_AnnualReturn2021	17.98%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	<span style="color:#000000;font-family:Times New Roman;font-size:9pt;margin-left:0.0pt;">Best Quarter:</span>
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	15.52%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	<span style="color:#000000;font-family:Times New Roman;font-size:9pt;margin-left:0.0pt;">Worst Quarter:</span>
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2020
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(18.16%)
1 Year	rr_AverageAnnualReturnYear01	17.98%
5 Years	rr_AverageAnnualReturnYear05	11.75%
Since Inception	rr_AverageAnnualReturnSinceInception	8.55%
Inception Date	rr_AverageAnnualReturnInceptionDate	Mar. 01, 2014
Class I2 | Transamerica Multi-Asset Income | Return After Taxes on Distributions | I2
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	16.33%
5 Years	rr_AverageAnnualReturnYear05	10.15%
Since Inception	rr_AverageAnnualReturnSinceInception	7.01%
Class I2 | Transamerica Multi-Asset Income | Return After Taxes on Distributions and Sale of Fund Shares | I2
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	11.12%
5 Years	rr_AverageAnnualReturnYear05	8.69%
Since Inception	rr_AverageAnnualReturnSinceInception	6.14%
Class I2 | Transamerica Multi-Asset Income | S&P 500® Index (reflects no deduction for fees, expenses or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	28.71%
5 Years	rr_AverageAnnualReturnYear05	18.47%
Since Inception	rr_AverageAnnualReturnSinceInception	14.96%
Class I2 | Transamerica Multi-Asset Income | Transamerica Multi-Asset Income Blended Benchmark (reflects no deduction for fees, expenses or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	18.64%	[3]
5 Years	rr_AverageAnnualReturnYear05	13.51%	[3]
Since Inception	rr_AverageAnnualReturnSinceInception	11.16%	[3]

[1] Acquired fund fees and expenses reflect the fund’s pro rata share of the fees and expenses incurred by investing in other investment companies. Acquired fund fees and expenses are not included in the calculation of the ratios of expenses to average net assets shown in the Financial Highlights section of the fund’s prospectus.

[2] TAM has contractually agreed to reimburse all acquired fund fees and expenses through March 1, 2023.

[3] The Transamerica Multi-Asset Income Blended Benchmark consists of the following: ICE BofAML U.S. High Yield BB-B Rated Constrained Index: 40% and S&P 500® Index: 60%. Calculations assume dividends and capital gains are reinvested and do not include any managerial expenses.