Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	COLUMBIA FUNDS SERIES TRUST I
Prospectus Date	rr_ProspectusDate	Oct. 01, 2013
Columbia Risk Allocation Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Summary of the Fund
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Columbia Risk Allocation Fund (the Fund) pursues consistent total returns by seeking to balance risks across multiple asset classes.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and members of your immediate family invest, or agree to invest in the future, at least $50,000 in certain classes of shares of eligible funds distributed by Columbia Management Investment Distributors, Inc. More information about these and other discounts is available from your financial intermediary, in the Choosing a Share Class section beginning on page 30 of the Fund’s prospectus and in Appendix S to the Statement of Additional Information (SAI) under Sales Charge Waivers beginning on page S-1.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	September 30, 2014
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund may pay 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. For the fiscal period from June 19, 2012 (commencement of operations) to May 31, 2013, the Fund’s portfolio turnover rate was 76% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	76.00%
Expense Breakpoint Discounts [Text]	rr_ExpenseBreakpointDiscounts	You may qualify for sales charge discounts if you and members of your immediate family invest, or agree to invest in the future, at least $50,000 in certain classes of shares of eligible funds distributed by Columbia Management Investment Distributors, Inc. More information about these and other discounts is available from your financial intermediary, in the Choosing a Share Class section beginning on page 30 of the Fund’s prospectus and in Appendix S to the Statement of Additional Information (SAI) under Sales Charge Waivers beginning on page S-1.
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 50,000
Expenses Restated to Reflect Current [Text]	rr_ExpensesRestatedToReflectCurrent	Other expenses for Class A, Class C, Class K, Class R, Class R5, Class W and Class Z have been restated to reflect contractual changes to certain fees paid by the Fund.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]	rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees	“Total annual Fund operating expenses” in the table (which includes acquired fund fees and expenses) may not match “Net Expenses” in the Financial Highlights section of this prospectus because it does not include such acquired fund fees and expenses.
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The following 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 illustrates the hypothetical expenses that you would incur over the time periods indicated, and assumes that: you invest $10,000 in the applicable class of Fund shares for the periods indicated, your investment has a 5% return each year, and the Fund’s total annual operating expenses remain the same as shown in the Annual Fund Operating Expenses table above. Since the waivers and/or reimbursements shown in the Annual Fund Operating Expenses table above expire as indicated in the preceding table, they are only reflected in the 1 year example and the first year of the other examples. Although your actual costs may be higher or lower, based on the assumptions listed above, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances, the Fund pursues its investment objective by allocating its investment risks across multiple asset class categories that may respond differently to various economic and market environments. Columbia Management Investment Advisers, LLC (the Investment Manager) employs a proprietary risk allocation process with the goal of generating attractive long-term risk-adjusted returns while being able to respond to shorter term changes in market volatility. Based on its allocation process, the Investment Manager invests the Fund's assets so that portfolio risk (measured by the Investment Manager's expectations regarding the volatility of each asset class) is allocated to equity securities, fixed income securities and inflation-hedging assets in a manner intended to generate attractive long-term risk-adjusted returns. Generally, the allocations of risk to these asset class categories are expected to be similar, but may differ based on various factors as measured by the Investment Manager, including its expectations regarding the volatility associated with each asset class category and the expected risk-adjusted returns of these asset class categories. “Inflation-hedging” assets may include, but are not limited to, direct or indirect investments in commodity-related investments, including certain types of commodities-linked derivatives, and U.S. and non-U.S. inflation-linked bonds. Within the general asset class categories of equity securities, fixed-income securities and inflation-hedging assets, the Investment Manager may establish market exposures to components of those asset classes, such as common stocks, preferred stocks, nominal and inflation-linked treasury bonds, corporate bonds, convertible securities, structured securities, commodities, real estate, currencies, cash and cash equivalents in an effort to improve the overall expected risk-adjusted returns of the Fund as assessed by the Investment Manager. The Investment Manager may use a variety of instruments to gain exposure to these asset classes including, but not limited to: equity and fixed income securities, convertible securities, futures, currency forwards, options, structured securities (including asset-backed securities, mortgage-backed securities and collateralized loan obligations), swaps, swaps on futures, exchange-traded funds (ETFs) (including both leveraged and inverse ETFs), exchange-traded notes (including both leveraged and inverse notes), sovereign debt obligations, repurchase agreements, reverse repurchase agreements, commodity-related investments, inflation-linked bonds, closed-end funds and real estate investment trusts. The Fund may invest in fixed income securities of any maturity (and does not seek to maintain a particular dollar-weighted average maturity) and of any credit quality, including investments that are rated below investment-grade (commonly referred to as “high yield securities” or “junk bonds”) or, if unrated, deemed by the Investment Manager to be of comparable quality. The Fund may invest without limitation in both developed and emerging market countries. The Fund may invest in companies that have market capitalizations of any size. The Fund may invest in derivatives for both hedging and non-hedging purposes, including, for example, seeking to enhance returns or as a substitute for a position in an underlying asset. The Fund may invest in derivatives to manage the Fund's overall risk exposure. The Fund may also use derivatives to obtain leverage (market exposure in excess of the Fund's assets). The Fund may utilize significant amounts of leverage within certain asset classes in order to maintain attractive expected risk-adjusted returns while adhering to the Fund's risk allocation framework. The Fund may also take short positions, for hedging or investment purposes, or in certain market conditions have no market positions (i.e., the Fund may hold only cash and cash equivalents) as determined by the Investment Manager. The Fund may hold a significant amount of cash, money market instruments (which may include investments in one or more affiliated or unaffiliated money market funds or similar vehicles), other high-quality, short-term investments, or other liquid assets to meet its segregation obligations as a result of its investments in derivatives. The Fund may invest in the securities and instruments described herein directly or indirectly through investments in other mutual funds and ETFs managed by the Investment Manager or its affiliates (such affiliated funds collectively, the Underlying Funds). In particular, the Fund currently expects to invest significantly in Columbia Absolute Return Enhanced Multi-Strategy Fund, Columbia Commodity Strategy Fund and Columbia Emerging Markets Fund but may also invest significantly in other Underlying Funds. Depending on current and expected market and economic conditions, the Fund may invest all of its assets in Underlying Funds. The Investment Manager has considerable flexibility in the construction of the portfolio and may change the asset class mix frequently, including from day to day. The Fund’s investment strategy may involve the frequent trading of portfolio securities. This may cause the Fund to incur higher transaction costs (which may adversely affect the Fund’s performance) and may increase taxable distributions for shareholders. The Fund is non-diversified, which means that it can invest a greater percentage of its assets in the securities of fewer issuers than can a diversified fund.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	An investment in the Fund involves risk, including those described below. There is no assurance that the Fund will achieve its investment objective and you may lose money. The value of the Fund’s holdings may decline, and the Fund’s net asset value (NAV) and Fund share price may go down. Active Management Risk. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives. The Fund may fail to achieve its investment objective and you may lose money. Allocation Risk. The Fund uses asset and risk allocation strategies in pursuit of its investment objective. There is a risk that the Fund’s allocation among asset classes or investments will cause the Fund’s shares to lose value or cause the Fund to underperform other funds with similar investment objectives, or that the investments themselves will not produce the returns expected. Although the Fund will pursue its objective by allocating investment risks (measured by volatility expectations) across asset classes that may react differently to various environments, there is no guarantee that it will be successful. Despite the Fund’s name, the Fund may be unsuccessful in allocating risk effectively. The portfolio managers may not correctly estimate expected returns, volatility and correlations of various asset classes, causing the Fund’s risk allocation methodology to fail to meet the Fund’s investment objective. Changing Distribution Level Risk. The amount of the distributions paid by the Fund will vary and generally depends on the amount of interest income and/or dividends received by the Fund on the securities it holds. The Fund may not be able to pay distributions or may have to reduce its distribution level if the interest income and/or dividends the Fund receives from its investments decline. Commodity Futures Trading Commission (CFTC) Regulatory Risk. The Fund does not qualify for an exemption from registration as a “commodity pool” under rules of the Commodity Exchange Act (the CEA). Accordingly, the Fund is a commodity pool under the CEA and the Investment Manager is registered as a “commodity pool operator” under the CEA. The Fund is subject to dual regulation by the SEC and the CFTC. Compliance with the CFTC’s regulatory requirements could increase Fund expenses, adversely affecting the Fund’s total return. Commodity-related Investment Risk. The value of commodities investments will generally be affected by overall market movements and factors specific to a particular industry or commodity, which may include demand for the commodity, weather, embargoes, tariffs, and economic health, political, international, regulatory and other developments. Exposure to commodities and commodities markets may subject the value of the Fund’s investments to greater volatility than other types of investments. Commodities investments may also subject the Fund to counterparty risk and liquidity risk. The Fund invests in an underlying fund that makes commodity-related investments through a wholly owned subsidiary organized outside the U.S. that is generally not subject to U.S. laws (including securities laws) and their protections. Commodity-related Tax Risk. If the Fund does not appropriately limit its commodity-related investments or if such investments are re-characterized for U.S. federal income tax purposes, the Fund may be unable to qualify as a regulated investment company for one or more years, which would adversely affect the value of the Fund (and the favorable tax treatment afforded to regulated investment companies). In this event, the Fund’s Board may authorize a significant change in investment strategy or the Fund’s liquidation. Convertible Securities Risk. Convertible securities are subject to the usual risks associated with debt securities, such as interest rate risk and credit risk. Convertible securities also react to changes in the value of the common stock into which they convert, and are thus subject to market risk. The Fund may also be forced to convert a convertible security at an inopportune time, which may decrease the Fund’s return. Credit Risk. Credit risk is the risk that the issuer of a fixed-income security may or will default or otherwise become unable or unwilling, or is perceived to be unable or unwilling, to honor a financial obligation, such as making payments to the Fund when due. If the Fund purchases unrated securities, or if the rating of a security is lowered after purchase, the Fund will depend on analysis of credit risk more heavily than usual. Unrated securities held by the Fund may present increased credit risk as compared to higher-rated securities Derivatives Risk. Losses involving derivative instruments may be substantial, because a relatively small movement in the price of an underlying security, instrument, commodity, currency or index may result in a substantial loss for the Fund. In addition to the potential for increased losses, the use of derivative instruments may lead to increased volatility within the Fund. Derivatives will typically increase the Fund’s exposure to principal risks to which it is otherwise exposed, and may expose the Fund to additional risks, including correlation risk, counterparty risk, hedging risk, leverage risk and liquidity risk. Derivatives Risk/Commodity-Linked Futures Contracts. The loss that may be incurred by the Fund in entering into futures contracts is potentially unlimited and may exceed the amount of the premium. Futures markets are highly volatile and the use of futures by the Fund may increase the volatility of the Fund’s net asset value. Additionally, as a result of the low collateral deposits normally required in futures trading, a relatively small price movement in a futures contract may result in substantial losses to the Fund. Futures contracts may be illiquid. The liquidity of the futures market depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants decide to make or take delivery, liquidity in the futures market could be reduced. Furthermore, exchanges may limit fluctuations in futures contract prices during a trading session by imposing a maximum permissible price movement on each futures contract. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. Moreover, to the extent the Fund engages in futures contracts on foreign exchanges, such exchanges may not provide the same protection as U.S. exchanges. Derivatives Risk/Commodity-Linked Structured Notes Risk. Investments in commodity-linked structured notes involve substantial risks, including risk of loss of interest and principal, lack of a liquid secondary market, and risk of greater volatility than investments in traditional equity and debt markets. These instruments involve additional risks, including counterparty risk and hedging risk. Derivatives Risk/Commodity-Linked Swaps Risk. Commodity-linked swaps could result in losses if the underlying asset (e.g., a particular commodity) or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of short swap transactions. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk) and are subject to counterparty risk, hedging risk, pricing risk and liquidity risk. Derivatives Risk/Forward Foreign Currency Contracts Risk. These instruments are a type of derivative contract whereby the Fund may agree to buy or sell a country’s or region’s currency at a specific price on a specific date in the future. These contracts may fall in value due to foreign market downswings or foreign currency value fluctuations. The Fund’s strategy of investing in these instruments may not be successful. Investment in these instruments also subjects the Fund to counterparty risk. Derivatives Risk/Futures Contracts Risk. The loss that may be incurred in entering into futures contracts may exceed the amount of the premium paid and may be potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Additionally, as a result of the low collateral deposits normally involved in futures trading, a relatively small price movement in a futures contract may result in substantial losses to the Fund. Futures contracts may be illiquid. Furthermore, exchanges may limit fluctuations in futures contract prices during a trading session by imposing a maximum permissible price movement on each futures contract. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. Futures contracts executed on foreign exchanges may not provide the same protection as U.S. exchanges. These transactions involve additional risks, including counterparty risk, hedging risk and pricing risk. Derivatives Risk/Options Risk. The use of options is a highly specialized activity which involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. If the Fund sells a put option, there is a risk that the Fund may be required to buy the underlying asset at a disadvantageous price. If the Fund sells a call option, there is a risk that the Fund may be required to sell the underlying asset at a disadvantageous price, and if the call option sold is not covered (for example, by owning the underlying asset), the Fund's losses are potentially unlimited. These transactions involve other risks, including counterparty risk and hedging risk. Derivatives Risk/Swaps Risk. The use of swaps is a highly specialized activity that involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. Swaps could result in losses if the underlying asset or reference does not perform as anticipated. The value of swaps, like many other derivatives, may move in unexpected ways and may result in losses for the Fund. Such transactions can have the potential for unlimited losses. Such risk is heightened in the case of short swap transactions involving short exposures. Swaps can involve greater risks than direct investment in the underlying asset, because swaps may be leveraged (creating leverage risk) and are subject to counterparty risk, hedging risk, pricing risk and liquidity risk. Emerging Market Securities Risk. Securities issued by foreign governments or companies in emerging market countries are more likely to have greater exposure to the risks of investing in foreign securities that are described in Foreign Securities Risk. In addition, emerging market countries are more likely to experience instability resulting, for example, from rapid changes or developments in social, political and economic conditions. Their economies are usually less mature and their securities markets are typically less developed with more limited trading activity (i.e., lower trading volumes and less liquidity) than more developed countries. Emerging market securities tend to be more volatile than securities in more developed markets. Many emerging market countries are heavily dependent on international trade and have fewer trading partners, which makes them more sensitive to world commodity prices and economic downturns in other countries, and some have a higher risk of currency devaluations. Foreign Currency Risk. The performance of the Fund may be materially affected positively or negatively by foreign currency strength or weakness relative to the U.S. dollar, particularly if the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar. Foreign Securities Risk. Investments in foreign securities involve certain risks not associated with investments in securities of U.S. companies. Foreign securities subject the Fund to the risks associated with investing in the particular country, including the political, regulatory, economic, social, diplomatic and other conditions or events occurring in the country or region, as well as risks associated with less developed custody and settlement practices. Foreign securities may be more volatile and less liquid than investments in securities of U.S. companies. The performance of the Fund may be negatively impacted by foreign currency strength or weakness relative to the U.S. dollar, particularly if the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar. Frequent Trading Risk. The portfolio managers may actively and frequently trade investments in the Fund's portfolio to carry out its investment strategies. Frequent trading of investments increases the possibility that the Fund, as relevant, will realize taxable capital gains (including short-term capital gains, which are generally taxable to shareholders at higher rates than long-term capital gains for U.S. federal income tax purposes), which could reduce the Fund's after-tax return. Frequent trading can also mean higher brokerage and other transaction costs, which could reduce the Fund's return. The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund’s performance. Inflation-Protected Securities Risk. Inflation-protected debt securities tend to react to changes in real interest rates (i.e., nominal interest rates minus the expected impact of inflation). In general, the price of such securities falls when real interest rates rise, and rises when real interest rates fall. Interest payments on these securities will vary and may be more volatile than interest paid on ordinary bonds. In periods of deflation, the Fund may have no income at all from such investments. Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt securities will tend to fall, and if interest rates fall, the values of debt securities will tend to rise. Changes in the value of a debt security usually will not affect the amount of income the Fund receives from it but may affect the value of the Fund's shares. In general, the longer the maturity or duration of a debt security, the greater its sensitivity to changes in interest rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk. As interest rates rise or spreads widen, the likelihood of prepayment decreases. Issuer Risk. An issuer in which the Fund invests may perform poorly, and the value of its securities may therefore decline, which would negatively affect the Fund’s performance. Poor performance may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters or other events, conditions or factors. Investing in Other Funds Risk. The Fund’s investment in other funds (affiliated and/or unaffiliated funds, including exchange-traded funds (ETFs)) subjects the Fund to the investment performance (positive or negative) and risks of these underlying funds in direct proportion to the Fund’s investment therein. The performance of underlying funds could be adversely affected if other entities that invest in the same underlying funds make relatively large investments or redemptions in such underlying funds. The Fund, and its shareholders, indirectly bear a portion of the expenses of any funds in which the Fund invests. Because the expenses and costs of a fund are shared by its investors, redemptions by other investors in the fund could result in decreased economies of scale and increased operating expenses for such fund. The Investment Manager may have potential conflicts of interest in selecting affiliated underlying funds for investment by the Fund because the fees paid to it by some underlying funds are higher than the fees paid by other underlying funds, as well as a potential conflict in selecting affiliated funds over unaffiliated funds. Leverage Risk. Leverage occurs when the Fund increases its assets available for investment using borrowings, short sales, derivatives, or similar instruments or techniques. The use of leverage may make any change in the Fund's NAV even greater and thus result in increased volatility of returns. Because short sales involve borrowing securities and then selling them, the Fund’s short sales effectively leverage the Fund’s assets. The Fund's assets that are used as collateral to secure the Fund's obligations to return the securities sold short may decrease in value while the short positions are outstanding, which may force the Fund to use its other assets to increase the collateral. Leverage can create an interest expense that may lower the Fund's overall returns. Leverage presents the opportunity for increased net income and capital gains, but also exaggerates the Fund's risk of loss. There can be no guarantee that a leveraging strategy will be successful. Liquidity Risk. Liquidity risk is the risk associated with a lack of marketability of investments which may make it difficult to sell the investment at a desirable time or price. The Fund may have to lower the selling price, sell other investments, or forego another, more appealing investment opportunity. Judgment plays a larger role in valuing these investments as compared to valuing more liquid investments. Low and Below Investment Grade (High-Yield) Securities Risk. Securities with the lowest investment grade rating, securities rated below investment grade (commonly called “high-yield” or “junk” bonds) and unrated securities of comparable quality expose the Fund to a greater risk of loss of principal and income than a fund that invests solely or primarily in investment grade securities. In addition, these investments have greater price fluctuations, are less liquid and are more likely to experience a default than higher-rated securities. High-yield securities are considered to be predominantly speculative with respect to the issuer’s capacity to pay interest and repay principal. Market Risk. Market risk refers to the possibility that the market values of securities or other investments that the Fund holds will fall, sometimes rapidly or unpredictably, or fail to rise. An investment in the Fund could lose money over short or even long periods. In general, equity securities tend to have greater price volatility than debt securities. Money Market Fund Investment Risk. An investment in a money market fund is not a bank deposit and is not insured or guaranteed by any bank, the FDIC or any other government agency. Although money market funds seek to preserve the value of investments at $1.00 per share, it is possible for the Fund to lose money by investing in money market funds. In addition to the fees and expenses that the Fund directly bears, the Fund indirectly bears the fees and expenses of any money market funds in which it invests, including affiliated money market funds. The Fund will also be exposed to the investment risks of the money market fund. To the extent the Fund invests in instruments such as derivatives, the Fund may hold investments, which may be significant, in money market fund shares to cover its obligations resulting from its investments in derivatives. Mortgage- and Other Asset-Backed Securities Risk. The value of any mortgage-backed and other asset-backed securities held by the Fund may be affected by, among other things, changes or perceived changes in: interest rates, factors concerning the interests in and structure of the issuer or the originator of the mortgages or other assets, the creditworthiness of the entities that provide any supporting letters of credit, surety bonds or other credit enhancements, or the market's assessment of the quality of underlying assets. Payment of principal and interest on some mortgage-backed securities (but not the market value of the securities themselves) may be guaranteed by the full faith and credit of the U.S. Government or by its agencies, authorities, enterprises or instrumentalities, which are not insured or guaranteed by the U.S. Government. Mortgage-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) may entail greater risk than obligations guaranteed by the U.S. Government. Mortgage-backed securities are subject to prepayment risk, which is the possibility that the underlying mortgage may be refinanced or prepaid prior to maturity during periods of declining or low interest rates, causing the Fund to have to reinvest the money received in securities that have lower yields. Rising or high interest rates tend to extend the duration of mortgage-backed securities, making their prices more volatile and more sensitive to changes in interest rates. Non-Diversified Fund Risk. The Fund is non-diversified, which generally means that it will invest a greater percentage of its total assets in the securities of fewer issuers than a “diversified” fund. This increases the risk that a change in the value of any one investment held by the Fund could affect the overall value of the Fund more than it would affect that of a diversified fund holding a greater number of investments. Accordingly, the Fund's value will likely be more volatile than the value of a more diversified fund. Preferred Stock Risk. Preferred stock is a type of stock that generally pays dividends at a specified rate and that has preference over common stock in the payment of dividends and the liquidation of assets. Preferred stock does not ordinarily carry voting rights. The price of a preferred stock is generally determined by earnings, type of products or services, projected growth rates, experience of management, liquidity, and general market conditions of the markets on which the stock trades. The most significant risks associated with investments in preferred stock include Issuer Risk, Market Risk and Interest Rate Risk (i.e., the risk of losses attributable to changes in interest rates). Prepayment and Extension Risk. Prepayment and extension risk is the risk that a loan, bond or other security or investment might be called or otherwise converted, prepaid or redeemed before maturity, and the portfolio managers may not be able to invest the proceeds in other investments providing as high a level of income, resulting in a reduced yield to the Fund. As interest rates decrease or spreads narrow, the likelihood of prepayment increases. The portfolio managers may be unable to capitalize on securities with higher interest rates or wider spreads because the Fund’s investments are locked in at a lower rate for a longer period of time. Quantitative Model Risk. Investments selected using quantitative methods may perform differently from the market as a whole. There can be no assurance that these methodologies will enable the Fund to achieve its objective. Real Estate-related Investment Risk. Investment in real estate investment trusts (REITs) and in securities of other companies (wherever organized) principally engaged in the real estate industry subjects the Fund to, among other risks, risks similar to those of direct investments in real estate and the real estate industry in general, including risks related to general and local economic conditions, possible lack of availability of financing and changes in interest rates or property values. REITs are entities that either own properties or make construction or mortgage loans, and also may include operating or finance companies. The value of REIT shares is affected by, among other factors, changes in the value of the underlying properties owned by the REIT, by changes in the prospect for earnings and/or cash flow growth of the REIT itself, defaults by borrowers or tenants, market saturation, decreases in market rates for rents, and other economic, political, or regulatory matters affecting the real estate industry, including REITs. REITs and similar non-U.S. entities depend upon specialized management skills, may have limited financial resources, may have less trading volume in their securities, and may be subject to more abrupt or erratic price movements than the overall securities markets. REITs are also subject to the risk of failing to qualify for tax-free pass-through of income. Some REITs (especially mortgage REITs) are affected by risks similar to those associated with investments in debt securities including changes in interest rates and the quality of credit extended. Reinvestment Risk. Reinvestment risk is the risk that the Fund will not be able to reinvest income or principal at the same return it is currently earning. Repurchase Agreements Risk. Repurchase agreements are agreements in which the seller of a security to the Fund agrees to repurchase that security from the Fund at a mutually agreed upon price and time. Repurchase agreements carry the risk that the counterparty may not fulfill its obligations under the agreement. This could cause the Fund's income and the value of your investment in the Fund to decline. Reverse Repurchase Agreements Risk. Reverse repurchase agreements are agreements in which a Fund sells a security to a counterparty, such as a bank or broker-dealer, in return for cash and agrees to repurchase that security at a mutually agreed upon price and time. Reverse repurchase agreements carry the risk that the market value of the security sold by the Fund may decline below the price at which the Fund must repurchase the security. Reverse repurchase agreements also may be viewed as a form of borrowing. Short Positions Risk. The Fund may establish short positions which introduce more risk to the Fund than long positions (where the Fund owns the instrument) because the maximum sustainable loss on an instrument purchased (held long) is limited to the amount paid for the instrument plus the transaction costs, whereas there is no maximum price of the shorted instrument when purchased in the open market. Therefore, in theory, short positions have unlimited risk. The Fund’s use of short positions in effect “leverages” the Fund. Leverage potentially exposes the Fund to greater risks of loss due to unanticipated market movements, which may magnify losses and increase the volatility of returns. To the extent the Fund takes a short position in a derivative instrument, this involves the risk of a potentially unlimited increase in the value of the underlying instrument. Small- and Mid-Cap Company Securities Risk. Investments in small- and mid-capitalization companies (small- and mid-cap companies) often involve greater risks than investments in larger, more established companies (larger companies) because small- and mid-cap companies tend to have less predictable earnings and may lack the management experience, financial resources, product diversification and competitive strengths of larger companies, and securities of small- and mid-cap companies may be less liquid and more volatile than the securities of larger companies. Sovereign Debt Risk. A sovereign debtor’s willingness or ability to repay principal and pay interest in a timely manner may be affected by a variety of factors, including its cash flow situation, the extent of its reserves, the availability of sufficient foreign exchange on the date a payment is due, the relative size of the debt service burden to the economy as a whole, the sovereign debtor’s policy toward international lenders, and the political constraints to which a sovereign debtor may be subject. Sovereign debt risk is increased for emerging market issuers. U.S. Government Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government.
Risk Lose Money [Text]	rr_RiskLoseMoney	There is no assurance that the Fund will achieve its investment objective and you may lose money.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	Non-Diversified Fund Risk. The Fund is non-diversified, which generally means that it will invest a greater percentage of its total assets in the securities of fewer issuers than a “diversified” fund. This increases the risk that a change in the value of any one investment held by the Fund could affect the overall value of the Fund more than it would affect that of a diversified fund holding a greater number of investments. Accordingly, the Fund's value will likely be more volatile than the value of a more diversified fund.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The Fund has not had a full calendar year of operations as of the date of this prospectus and therefore performance information is not available. When available, the Fund intends to compare its performance to the performance of the Citigroup 3-month U.S. Treasury Bill Index, which is an unmanaged index that represents the performance of three-month Treasury bills and reflects reinvestment of all distributions and changes in market prices. The Fund also intends to compare its performance to the performance of a Blended Benchmark, which is a weighted custom composite, established by the Investment Manager, consisting of a 60% weighting of the S&P 500® Index and a 40% weighting of the Barclays U.S. Aggregate Bond Index because the Investment Manager believes that the Blended Benchmark provides an additional useful performance comparison. The S&P 500® Index tracks the performance of 500 widely held, large-capitalization U.S. stocks, and the Barclays U.S. Aggregate Bond Index is a market value-weighted index that tracks the daily price, coupon, pay-downs and total return performance of fixed-rate, publicly placed, dollar-denominated and non-convertible investment grade debt issues with at least $250 million par amount outstanding and with at least one year to final maturity. Updated performance information can be obtained by calling toll-free 800.345.6611 or visiting columbiamanagement.com.
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	The Fund has not had a full calendar year of operations as of the date of this prospectus and therefore performance information is not available.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	800.345.6611
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	columbiamanagement.com
Columbia Risk Allocation Fund | Class A
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a % of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	5.75%
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[1]
Management fees	rr_ManagementFeesOverAssets	0.41%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	1.25%	[2]
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.38%
Total annual Fund operating expenses	rr_ExpensesOverAssets	2.29%	[3]
Less: Fee waivers and/or expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(1.16%)	[4]
Total annual Fund operating expenses after fee waivers and/or expense reimbursements	rr_NetExpensesOverAssets	1.13%
Expenses Deferred Charges [Text Block]	rr_ExpensesDeferredChargesTextBlock	This charge is imposed on certain investments of between $1 million and $50 million redeemed within 18 months of purchase, as follows: 1.00% if redeemed within 12 months of purchase, and 0.50% if redeemed more than 12, but less than 18, months after purchase, with certain limited exceptions.
1 year	rr_ExpenseExampleYear01	684
3 years	rr_ExpenseExampleYear03	1,144
5 years	rr_ExpenseExampleYear05	1,630
10 years	rr_ExpenseExampleYear10	2,965
1 year	rr_ExpenseExampleNoRedemptionYear01	684
3 years	rr_ExpenseExampleNoRedemptionYear03	1,144
5 years	rr_ExpenseExampleNoRedemptionYear05	1,630
10 years	rr_ExpenseExampleNoRedemptionYear10	2,965
Columbia Risk Allocation Fund | Class C
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a % of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[5]
Management fees	rr_ManagementFeesOverAssets	0.41%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	1.25%	[2]
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.38%
Total annual Fund operating expenses	rr_ExpensesOverAssets	3.04%	[3]
Less: Fee waivers and/or expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(1.16%)	[4]
Total annual Fund operating expenses after fee waivers and/or expense reimbursements	rr_NetExpensesOverAssets	1.88%
Expenses Deferred Charges [Text Block]	rr_ExpensesDeferredChargesTextBlock	This charge applies to redemptions within one year of purchase, with certain limited exceptions.
1 year	rr_ExpenseExampleYear01	291
3 years	rr_ExpenseExampleYear03	830
5 years	rr_ExpenseExampleYear05	1,495
10 years	rr_ExpenseExampleYear10	3,274
1 year	rr_ExpenseExampleNoRedemptionYear01	191
3 years	rr_ExpenseExampleNoRedemptionYear03	830
5 years	rr_ExpenseExampleNoRedemptionYear05	1,495
10 years	rr_ExpenseExampleNoRedemptionYear10	3,274
Columbia Risk Allocation Fund | Class K
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a % of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.41%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	1.53%	[2]
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.38%
Total annual Fund operating expenses	rr_ExpensesOverAssets	2.32%	[3]
Less: Fee waivers and/or expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(1.31%)	[4]
Total annual Fund operating expenses after fee waivers and/or expense reimbursements	rr_NetExpensesOverAssets	1.01%
1 year	rr_ExpenseExampleYear01	103
3 years	rr_ExpenseExampleYear03	599
5 years	rr_ExpenseExampleYear05	1,121
10 years	rr_ExpenseExampleYear10	2,555
1 year	rr_ExpenseExampleNoRedemptionYear01	103
3 years	rr_ExpenseExampleNoRedemptionYear03	599
5 years	rr_ExpenseExampleNoRedemptionYear05	1,121
10 years	rr_ExpenseExampleNoRedemptionYear10	2,555
Columbia Risk Allocation Fund | Class R
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a % of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.41%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other expenses	rr_OtherExpensesOverAssets	1.25%	[2]
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.38%
Total annual Fund operating expenses	rr_ExpensesOverAssets	2.54%	[3]
Less: Fee waivers and/or expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(1.16%)	[4]
Total annual Fund operating expenses after fee waivers and/or expense reimbursements	rr_NetExpensesOverAssets	1.38%
1 year	rr_ExpenseExampleYear01	141
3 years	rr_ExpenseExampleYear03	680
5 years	rr_ExpenseExampleYear05	1,246
10 years	rr_ExpenseExampleYear10	2,788
1 year	rr_ExpenseExampleNoRedemptionYear01	141
3 years	rr_ExpenseExampleNoRedemptionYear03	680
5 years	rr_ExpenseExampleNoRedemptionYear05	1,246
10 years	rr_ExpenseExampleNoRedemptionYear10	2,788
Columbia Risk Allocation Fund | Class R5
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a % of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.41%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	1.28%	[2]
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.38%
Total annual Fund operating expenses	rr_ExpensesOverAssets	2.07%	[3]
Less: Fee waivers and/or expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(1.31%)	[4]
Total annual Fund operating expenses after fee waivers and/or expense reimbursements	rr_NetExpensesOverAssets	0.76%
1 year	rr_ExpenseExampleYear01	78
3 years	rr_ExpenseExampleYear03	522
5 years	rr_ExpenseExampleYear05	993
10 years	rr_ExpenseExampleYear10	2,296
1 year	rr_ExpenseExampleNoRedemptionYear01	78
3 years	rr_ExpenseExampleNoRedemptionYear03	522
5 years	rr_ExpenseExampleNoRedemptionYear05	993
10 years	rr_ExpenseExampleNoRedemptionYear10	2,296
Columbia Risk Allocation Fund | Class W
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a % of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.41%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	1.25%	[2]
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.38%
Total annual Fund operating expenses	rr_ExpensesOverAssets	2.29%	[3]
Less: Fee waivers and/or expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(1.16%)	[4]
Total annual Fund operating expenses after fee waivers and/or expense reimbursements	rr_NetExpensesOverAssets	1.13%
1 year	rr_ExpenseExampleYear01	115
3 years	rr_ExpenseExampleYear03	604
5 years	rr_ExpenseExampleYear05	1,119
10 years	rr_ExpenseExampleYear10	2,536
1 year	rr_ExpenseExampleNoRedemptionYear01	115
3 years	rr_ExpenseExampleNoRedemptionYear03	604
5 years	rr_ExpenseExampleNoRedemptionYear05	1,119
10 years	rr_ExpenseExampleNoRedemptionYear10	2,536
Columbia Risk Allocation Fund | Class Z
Risk/Return:	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a % of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.41%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	1.25%	[2]
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.38%
Total annual Fund operating expenses	rr_ExpensesOverAssets	2.04%	[3]
Less: Fee waivers and/or expense reimbursements	rr_FeeWaiverOrReimbursementOverAssets	(1.16%)	[4]
Total annual Fund operating expenses after fee waivers and/or expense reimbursements	rr_NetExpensesOverAssets	0.88%
1 year	rr_ExpenseExampleYear01	90
3 years	rr_ExpenseExampleYear03	527
5 years	rr_ExpenseExampleYear05	991
10 years	rr_ExpenseExampleYear10	2,276
1 year	rr_ExpenseExampleNoRedemptionYear01	90
3 years	rr_ExpenseExampleNoRedemptionYear03	527
5 years	rr_ExpenseExampleNoRedemptionYear05	991
10 years	rr_ExpenseExampleNoRedemptionYear10	$ 2,276

[1] This charge is imposed on certain investments of between $1 million and $50 million redeemed within 18 months of purchase, as follows: 1.00% if redeemed within 12 months of purchase, and 0.50% if redeemed more than 12, but less than 18, months after purchase, with certain limited exceptions.

[2] Other expenses for Class A, Class C, Class K, Class R, Class R5, Class W and Class Z have been restated to reflect contractual changes to certain fees paid by the Fund.

[3] “Total annual Fund operating expenses” in the table (which includes acquired fund fees and expenses) may not match “Net Expenses” in the Financial Highlights section of this prospectus because it does not include such acquired fund fees and expenses.

[4] Columbia Management Investment Advisers, LLC and certain of its affiliates have contractually agreed to waive fees and/or to reimburse expenses (excluding certain fees and expenses, such as transaction costs and certain other investment related expenses, interest, taxes, acquired fund fees and expenses, and extraordinary expenses) until September 30, 2014, unless sooner terminated at the sole discretion of the Fund’s Board of Trustees. Under this agreement, the Fund’s net operating expenses, subject to applicable exclusions, will not exceed the annual rates of 0.75% for Class A, 1.50% for Class C, 0.63% for Class K, 1.00% for Class R, 0.38% for Class R5, 0.75% for Class W and 0.50% for Class Z.

[5] This charge applies to redemptions within one year of purchase, with certain limited exceptions.