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 46% of the average value of its portfolio.

Portfolio Turnover, Rate

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46.00%

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’s sub-adviser, Kayne Anderson Capital Advisors, L.P. (the “sub-adviser”), seeks to achieve the fund’s stated objective by investing at least 80% of the fund’s net assets (plus the amount of borrowings, if any, for investment purposes) in the equity and debt securities of energy master limited partnerships (“MLPs”), MLP-related entities, energy infrastructure companies and other issuers in the energy sector. The sub-adviser considers the “energy sector” to consist of companies involved in exploring, developing, producing, generating, transporting, transmitting, storing, gathering, processing, refining, distributing, mining or marketing of natural gas, natural gas liquids, crude oil, refined products, coal or electricity (“energy-related assets”).

MLPs are publicly traded partnerships that principally own and operate assets used in energy logistics, including, but not limited to, assets used in transporting, storing, gathering, processing, distributing, or marketing of natural gas, natural gas liquids, crude oil or refined products (“midstream assets”). MLPs also include general partner MLPs whose assets consist of ownership interests of an affiliated MLP (which may include general partnership interests, incentive distribution rights, common units and subordinated units).

MLP-related entities include companies structured as MLPs that have elected to be taxed as corporations for federal income tax purposes, affiliates of MLPs, substantially all of whose assets consist of i-units and instruments that are derivatives of interests in MLPs. MLP affiliates are not treated as publicly traded partnerships for federal income tax purposes. Energy infrastructure companies are companies, other than MLPs, that own or operate midstream assets. This includes companies that (i) derive at least 50% of their revenues or operating income from midstream assets or (ii) have midstream assets that represent a majority of their assets. Energy infrastructure companies are not structured as MLPs and are taxed as corporations. Investments in other issuers in the energy sector will consist of companies that own, operate or provide services to energy-related assets.

Equity investments by the fund may include securities of any capitalization that are publicly traded on an exchange or in the over-the-counter market, including MLP and limited liability company common units; the equity securities issued by MLP-related entities, such as I-shares of MLP-related entities and common shares of corporations that own, directly or indirectly, MLP general partner interests; and other investment companies that invest in MLPs and energy infrastructure companies.

The fund may invest in the debt securities of issuers in the energy sector, but not more than 10% of its total assets may be invested in debt securities that are rated below investment grade (commonly known as “junk bonds”), including defaulted securities.

The fund may directly invest up to, but not more than, 25% of its total assets in equity or debt securities of MLPs and other entities that are treated as qualified publicly traded partnerships for federal income tax purposes. This limit does not apply to I-shares of MLP-related entities, substantially all of whose assets consist of limited partnership interests in MLPs in the form of i-units, which are not treated as publicly traded partnerships for federal income tax purposes. MLP-related entities receive additional i-units in an amount equal to the cash distributions received by MLP common units. Similarly, holders of I-shares will receive additional I-shares, in the same proportion as the MLP-related entities’ receipt of i-units, rather than cash distributions.

The fund may use short sales, arbitrage and other strategies to try to generate additional return, the maximum exposure to which may not exceed 20% of the fund’s net assets. As part of such strategies, the fund may (1) engage in paired long short trades in an attempt to arbitrage pricing disparities in securities held in the fund (e.g., establishing a long or short position in the equity of an MLP issuer while simultaneously establishing an opposite position in an affiliated MLP-related entity or other affiliated equity security); (2) trade call or put options; (3) enter into total return swaps or credit default contracts; or (4) sell securities short. The fund may also invest in foreign securities, but generally will not invest more than 10% of fund assets in foreign securities. The fund only invests in securities traded on U.S. and Canadian exchanges.

Options trading is not a core strategy of the fund, but may be used to monetize existing positions when price targets are reached, to generate income and to help hedge the fund. In addition, by taking both long and short positions, the fund seeks to provide some protection in down markets when compared to a fund that takes only long positions.

The fund may invest a significant portion of its assets in cash, cash equivalent securities or short-term debt securities, repurchase agreements and money market instruments to serve as collateral for the positions the fund takes, to earn income, and for cash management purposes.

The above investment restrictions apply at the time of purchase, and the fund will not be required to reduce a position due solely to market value fluctuations in order to comply with these restrictions.

The fund is non-diversified.

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.

Arbitrage – Securities purchased pursuant to an arbitrage strategy intended to take advantage of a perceived relationship between the value of two or more securities may not perform as expected.

Capital Markets – Energy companies may be unable to obtain new debt or equity financing on acceptable terms. If funding is not available when needed, or is available only on unfavorable terms, energy companies may not be able to meet their obligations as they come due. Moreover, without adequate funding, energy companies may be unable to execute their growth strategies, complete future acquisitions, take advantage of other business opportunities or respond to competitive pressures, any of which could have a material adverse effect on their revenues and results of operations.

Cash Flow – A substantial portion of the income received by the fund is expected to be derived from investments in equity securities of energy companies. The amount and tax characterization of cash that any such company has available for distribution depends on the amount of cash generated from such company’s operations. Cash from operations may vary widely from quarter to quarter and is largely dependent on factors affecting the company’s operations and factors affecting the energy industry in general. In addition, operating costs, capital expenditures, acquisition costs, construction costs, exploration costs, borrowing costs and other costs of expenditures may reduce the amount of cash that a company has available for distribution in a given period.

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.

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.

Derivatives – Using derivatives exposes the fund to additional risks and can increase fund losses and reduce opportunities for gains when market prices, interest rates or the derivatives themselves behave in a way not anticipated by the fund. Using derivatives also can have a leveraging effect and increase fund volatility. The fund may also have to sell assets at inopportune times to satisfy its obligations. Derivatives may be difficult to sell, unwind or value, and the counterparty may default on its obligations to the fund. The fund's investments in derivative instruments may involve a small investment relative to the amount of investment exposure assumed and may result in losses exceeding the amounts invested in those instruments. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. The U.S. government is in the process of adopting and implementing regulations governing derivatives markets, including mandatory clearing of certain derivatives, margin and reporting requirements. The ultimate impact of the regulations remains unclear. Additional regulation of derivatives may make them more costly, may limit their availability, may disrupt markets or may otherwise adversely affect their value or performance.

Distressed or Defaulted Securities – Investments in defaulted securities and obligations of distressed issuers, including securities that are, or may be, involved in reorganizations or other financial restructurings, either out of court or in bankruptcy, involve substantial risks and are considered speculative. The fund may suffer significant losses if the reorganization or restructuring is not completed as anticipated. The fund will generally not receive interest payments on the distressed securities and may incur costs to protect its investment. Repayment of defaulted securities and obligations of distressed issuers is subject to significant uncertainties.

Energy Sector – Under normal circumstances, the fund concentrates its investments in industries in the energy sector. Investing in the energy sector involves a number of risks, including:

Supply and Demand. A decrease in the production of natural gas, natural gas liquids, crude oil, coal or other energy commodities, a decrease in the volume of such commodities available for transportation, mining, processing, storage or distribution or a sustained decline in demand for such commodities, may adversely impact the financial performance of energy companies.

Depletion and Exploration. Energy reserves naturally deplete as they are consumed over time. The financial performance of energy companies may be adversely affected if they, or the companies to whom they provide services, are unable to cost-effectively acquire additional energy deposits sufficient to replace the natural decline of existing reserves. Also, the quantities of reserves may be overstated, or deposits may not be produced in the time periods anticipated.

Regulatory. Energy companies are subject to significant federal, state and local government regulation in virtually every aspect of their operations, including (i) how facilities are constructed, maintained and operated, (ii) how and where wells are drilled, (iii) how services are provided, (iv) environmental and safety controls, and (v) the prices they may charge for the products and services they provide.

Commodity Pricing. The operations and financial performance of energy companies may be directly affected by energy commodity prices, especially those energy companies which own the underlying energy commodity or receive payments for services that are based on commodity prices.

Acquisition. The ability of energy companies to grow operating cash flow and increase such company’s enterprise value can be highly dependent on their ability to make accretive acquisitions. In the event that energy companies are unable to make such acquisitions, whether because they are unable to identify attractive acquisition candidates and negotiate and close acceptable purchase contracts or to raise financing for such acquisitions on economically acceptable terms, or otherwise, their future growth may be limited.

Affiliated Party. Certain energy companies are dependent on their parents or sponsors for a majority of their revenues. Any failure by such company’s parents or sponsors to satisfy their payments or obligations would impact such company’s revenues and operating cash flows and ability to make interest payments and/or distributions.

Catastrophe . The operations of energy companies are subject to many hazards inherent in the exploring, developing, producing, generating, transporting, transmission, storing, gathering, processing, refining, distributing, mining or marketing of natural gas, natural gas liquids, crude oil, refined products, coal or electricity, including: damage to pipelines, storage tanks, plants or related equipment and surrounding properties caused by hurricanes, tornadoes, floods, fires and other natural disasters or by acts of terrorism; inadvertent damage from construction and farm equipment; well blowouts; leaks of such energy commodities; fires and explosions.

Terrorism/Market Disruption. Events in the Middle East and elsewhere could have significant adverse effects on the U.S. economy, financial and commodities markets.

Weather . Extreme weather conditions, such as hurricanes, (i) could result in substantial damage to the facilities of certain energy companies located in the affected areas, (ii) significantly increase the volatility in the supply of energy commodities and (iii) adversely affect the financial performance of energy companies, and could therefore adversely affect their securities. The damage done by extreme weather also may serve to increase many insurance premiums paid by energy companies and could adversely affect such companies’ financial condition.

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.

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.

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.

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.

Industry Concentration – The fund concentrates its investments in a specific industry or industries. Concentration in a particular industry subjects the fund to the risks associated with that industry. As a result, the fund may be subject to greater price volatility and risk of loss as a result of adverse economic, business or other developments affecting that industry than funds investing in a broader range of industries.

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. The yields for equity securities of MLPs and certain midstream companies (companies that own and operate midstream assets, which are used in energy logistics, including, assets used in transporting, storing, gathering, processing, distributing, or marketing of natural gas, natural gas liquids, crude oil or refined products) are susceptible in the short-term to fluctuations in interest rates and the prices of such equity securities may decline when interest rates rise. This is also true for investments in debt instruments of energy companies. Rising interest rates can adversely impact the financial performance of energy companies by increasing the cost of capital. This may reduce such companies’ ability to execute acquisitions or expansion projects in a cost-effective manner.

IPOs – Initial public offerings (“IPOs”) are subject to specific risks which include, among others:

high volatility;

no track record for consideration;

securities may be illiquid; and

earnings are less predictable.

Leveraging – The value of your investment may be more volatile to the extent that the fund borrows or uses derivatives or other investments that have a leveraging effect on the fund. Other risks also will be compounded. This is because leverage generally magnifies the effect of a change in the value of an asset and creates a risk of loss of value on a larger pool of assets than the fund would otherwise have had. The use of leverage is considered to be a speculative investment practice and may result in the loss of a substantial amount, and possibly all, of the fund's assets. The fund also may have to sell assets at inopportune times to satisfy its obligations.

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.

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.

Master Limited Partnerships – Investments in MLPs involve risks that differ from investments in corporate issuers, including risks related to limited control and limited rights to vote on matters affecting the MLP, risks related to potential conflicts of interest between the MLP and the MLP’s general partner, cash flow risks, dilution risks, certain tax risks, and risks related to the general partner’s right to require unitholders to sell their common units at an undesirable time or price. MLP entities are typically focused in the energy, natural resources and real estate sectors of the economy. A downturn in the energy, natural resources or real estate sectors of the economy could have an adverse impact on the fund. At times, the performance of securities of companies in the energy, natural resources and real estate sectors of the economy may lag the performance of other sectors or the broader market as a whole. The yields for equity and debt securities of MLPs and other issuers in the energy sector are susceptible in the short-term to fluctuations in interest rates and the value of the fund’s investments in such securities may decline if interest rates rise. The value of the fund’s investment in MLPs depends to a significant extent on the MLPs being treated as partnerships for U.S. federal income tax purposes. If an MLP does not meet the legal requirements to maintain partnership status, it could be taxed as a corporation and there could be a material decrease in the value of its securities.

Non-Diversification – The fund is classified as “non-diversified,” which means it may invest a larger percentage of its assets in a smaller number of issuers than a diversified fund. To the extent the fund invests its assets in a smaller number of issuers, the fund will be more susceptible to negative events affecting those issuers than a diversified fund.

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.

Privately Held Companies – Privately held companies are not subject to SEC reporting requirements, are not required to maintain their accounting records in accordance with generally accepted accounting principles, and are not required to maintain effective internal controls over financial reporting. As a result, the sub-adviser may not have timely or accurate information about the business, financial condition and results of operations of the privately held companies in which the fund invests.

Repurchase Agreements – If the other party to a repurchase agreement defaults on its obligation, the fund may suffer delays and incur costs or lose money in exercising its rights under the agreement. If the seller fails to repurchase the security and the market value declines, the fund could lose money. If the seller becomes insolvent and subject to liquidation or reorganization under applicable bankruptcy or other laws, the fund's ability to dispose of the underlying securities may be restricted.

Short Sales – A short sale may be effected by selling a security that the fund does not own. If the price of the security sold short increases, the fund would incur a loss; conversely, if the price declines, the fund will realize a gain. Although the gain is limited by the price at which the security was sold short, the loss is potentially unlimited. The fund may also pay transaction costs and borrowing fees in connection with short sales.

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

Tax – In order to qualify for treatment as a regulated investment company (“RIC”) under the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”), the fund must meet certain requirements regarding the composition of its income, the diversification of its assets, and the amounts of its distributions. If the fund were to fail to meet any of these requirements, the fund might not be eligible for treatment as a RIC, in which case it would be subject to federal income tax on its net income at regular corporate rates (without reduction for distributions to shareholders). When distributed, that income would generally be taxable to shareholders as ordinary dividend income to the extent attributable to the fund’s earnings and profits. If the fund were to fail to qualify as a RIC, shareholders of the fund could realize significantly diminished returns from their investment in the fund. In the alternative, the fund may be able to preserve its RIC qualification under those circumstances by meeting certain conditions, in which case it may be subject to certain additional taxes.

The fund may invest no more than 25% of its total assets in the securities of MLPs and other entities treated as qualified publicly traded partnerships for federal income tax purposes. An MLP is an entity treated as a partnership under the Internal Revenue Code, the partnership interests of which are traded on securities exchanges like shares of corporate stock. To qualify as an MLP, an entity must receive at least 90% of its income from qualifying sources such as interest, dividends, income and gain from mineral or natural resources activities, income and gain from the transportation or storage of certain fuels, and, in certain circumstances, income and gain from commodities or futures, forwards and options with respect to commodities. For this purpose, mineral or natural resources activities include exploration, development, production, mining, refining, marketing and transportation (including pipelines) of oil and gas, minerals, geothermal energy, fertilizer, timber or industrial source carbon dioxide. If it does not so qualify, it will generally be subject to tax as a corporation and there could be a material decrease in the value of its securities.

Depreciation or other cost recovery deductions passed through to the fund from investments in MLPs in a given year will generally reduce the fund’s taxable income, but those deductions may be recaptured in the fund’s income in one or more subsequent years. When recognized and distributed, recapture income will generally be taxable to shareholders at the time of the distribution at ordinary income tax rates, even though those shareholders might not have held shares in the fund at the time the deductions were taken by the fund, and even though those shareholders may not have corresponding economic gain on their shares at the time of the recapture. In order to distribute recapture income or to fund redemption requests, the fund may need to liquidate investments, which may lead to additional recapture income.

Changes in tax laws or regulations, or interpretations thereof in the future, could adversely affect the fund or the issuers in which the fund invests. Any such changes could negatively impact the value of the fund’s investments and the amount and tax characterization of distributions paid by the fund.

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.

Risk Nondiversified Status [Text]

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Non-Diversification – The fund is classified as “non-diversified,” which means it may invest a larger percentage of its assets in a smaller number of issuers than a diversified fund. To the extent the fund invests its assets in a smaller number of issuers, the fund will be more susceptible to negative events affecting those issuers than a diversified 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 the fund’s performance for the past calendar 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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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:	06/30/2014	13.87%
Worst Quarter:	12/31/2014	-10.81%

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 Transamerica MLP & Energy Income Blended Benchmark consists of the following: Alerian MLP Index, 50% and Barclays Investment Grade Credit Index, 50%. Calculations assume dividends and capital gains are reinvested and do not include any managerial expenses.

Performance Table Closing [Text Block]

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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 MLP & Energy Income | 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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1.08%