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Risk/Return: rr_RiskReturnAbstract  
Registrant Name dei_EntityRegistrantName COLUMBIA FUNDS SERIES TRUST I
Prospectus Date rr_ProspectusDate Mar. 01, 2018
Columbia Strategic New York Municipal Income 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 Strategic New York Municipal Income Fund (the Fund) seeks total return, with a focus on income exempt from federal income tax and New York individual income tax and capital appreciation.
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. An investor transacting in a class of Fund shares without any front-end sales charge, contingent deferred sales charge, or other asset-based fee for sales or distribution may be required to pay a commission to the financial intermediary for effecting such transactions. Such commission rates are set by the financial intermediary and are not reflected in the tables or the example below. 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. (the Distributor). More information about these and other sales charge discounts and waivers is available from your financial intermediary, and can be found in the Choosing a Share Class section beginning on page 28 of the Fund’s prospectus, in Appendix A to the prospectus beginning on page A-1 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 February 28, 2019
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. During the most recent fiscal year, the Fund’s portfolio turnover rate was 7% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 7.00%
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. (the Distributor). More information about these and other sales charge discounts and waivers is available from your financial intermediary, and can be found in the Choosing a Share Class section beginning on page 28 of the Fund’s prospectus, in Appendix A to the prospectus beginning on page A-1 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 have been restated to reflect current transfer agency fees paid by the Fund and other expenses for Class Inst3 shares are based on estimated amounts for the Fund’s current fiscal year.
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 invests at least 80% of its net assets (including the amount of any borrowings for investment purposes) in municipal bonds that pay interest exempt from U.S. federal income tax (including the federal alternative minimum tax) and New York individual income tax. The Fund may invest in municipal debt instruments of any duration, maturity and credit quality, including below investment grade debt (commonly referred to as “high yield” investments or “junk” bonds). The Fund may invest up to 20% of its net assets in debt instruments that generate income subject to federal income tax, including the federal alternative minimum tax.

For purposes of the Fund’s 80% investment policy, these bonds and other debt instruments include those issued by or on behalf of the State of New York and its political subdivisions, agencies, authorities and instrumentalities, as well as by or on behalf of other qualified issuers, including those of U.S. territories, commonwealths and possessions, such as Guam, Puerto Rico and the U.S. Virgin Islands. The Fund may also invest in securities of other open-end or closed-end investment companies, including exchange-traded funds and municipal bond money market funds, that invest primarily in the types of debt instruments in which the Fund may invest directly. Given the flexible investment approach of the Fund, its maturity, duration, credit quality and sector allocations may fluctuate.

The Fund may invest in debt instruments of any maturity and does not seek to maintain a particular dollar-weighted average maturity.

The Fund may also invest in zero-coupon bonds.

The Fund may invest in derivatives such as futures (including interest rate futures and other bond futures) for purposes of yield curve exposure and for hedging purposes, and inverse floaters, for the purpose of enhancing income.

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 risks, 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 share price may go down. 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.

Active Management Risk. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies.

Changing Distribution Level Risk. The Fund will normally receive income which may include interest, dividends and/or capital gains, depending upon its investments. The amount of the distributions the Fund pays will vary and generally depends on the amount of income the Fund earns (less expenses) on its portfolio holdings, and capital gains or losses it recognizes. A decline in the Fund’s income or net capital gains from its investments may reduce its distribution level.

Closed-End Investment Company Risk. Closed-end investment companies frequently trade at a discount to their NAV, which may affect whether the Fund will realize gain or loss upon its sale of the closed-end investment company’s shares. Closed-end investment companies may employ leverage, which also subjects the closed-end investment company to increased risks such as increased volatility.

Counterparty Risk. Counterparty risk is the risk that a counterparty to a transaction in a financial instrument held by the Fund or by a special purpose or structured vehicle invested in by the Fund may become insolvent or otherwise fail to perform its obligations. As a result, the Fund may obtain no or limited recovery of its investment, and any recovery may be significantly delayed.

Credit Risk. Credit risk is the risk that the value of debt instruments may decline if the issuer thereof defaults or otherwise becomes unable or unwilling, or is perceived to be unable or unwilling, to honor its financial obligations, such as making payments to the Fund when due. Debt instruments backed by an issuer's taxing authority may be subject to legal limits on the issuer's power to increase taxes or otherwise to raise revenue, or may be dependent on legislative appropriation or government aid. Certain debt instruments are backed only by revenues derived from a particular project or source, rather than by an issuer's taxing authority, and thus may have a greater risk of default. Rating agencies assign credit ratings to certain debt instruments to indicate their credit risk. Unless otherwise provided in the Fund’s Principal Investment Strategies, investment grade debt instruments are those rated at or above BBB- by Standard and Poor’s Ratings Services, or equivalently rated by Moody’s Investors Service, Inc. or Fitch, Inc., or, if unrated, determined to be of comparable quality. Conversely, below investment grade (commonly called “high-yield” or “junk”) debt instruments are those rated below BBB- (or its equivalent) by such agencies or, if unrated, determined to be of comparable quality. A rating downgrade by such agencies can negatively impact the value of such instruments. Lower quality or unrated instruments held by the Fund may present increased credit risk as compared to higher-rated instruments. Non-investment grade debt instruments may be subject to greater price fluctuations and are more likely to experience a default than investment grade debt instruments and therefore may expose the Fund to increased credit risk. If the Fund purchases unrated instruments, or if the ratings of instruments held by the Fund are lowered after purchase, the Fund will depend on analysis of credit risk more heavily than usual.

Derivatives Risk. Derivatives may involve significant risks. Derivatives are financial instruments with a value in relation to, or derived from, the value of an underlying asset(s) or other reference, such as an index, rate or other economic indicator (each an underlying reference). Derivatives may include those that are privately placed or otherwise exempt from SEC registration, including certain Rule 144A eligible securities. Derivatives could result in Fund losses if the underlying reference does not perform as anticipated. Use of derivatives is a highly specialized activity that can involve investment techniques, risks, and tax planning different from those associated with more traditional investment instruments. The Fund’s derivatives strategy may not be successful and use of certain derivatives could result in substantial, potentially unlimited, losses to the Fund regardless of the Fund’s actual investment. A relatively small movement in the price, rate or other economic indicator associated with the underlying reference may result in substantial loss for the Fund. Derivatives may be more volatile than other types of investments. The value of derivatives may be influenced by a variety of factors, including national and international political and economic developments. Potential changes to the regulation of the derivatives markets may make derivatives more costly, may limit the market for derivatives, or may otherwise adversely affect the value or performance of derivatives. Derivatives can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Derivatives Risk – Futures Contracts Risk. A futures contract is an exchange-traded derivative transaction between two parties in which a buyer (holding the “long” position) agrees to pay a fixed price (or rate) at a specified future date for delivery of an underlying reference from a seller (holding the “short” position). The seller hopes that the market price on the delivery date is less than the agreed upon price, while the buyer hopes for the contrary. Certain futures contract markets are highly volatile, and futures contracts may be illiquid. Futures exchanges may limit fluctuations in futures contract prices by imposing a maximum permissible daily price movement. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. At or prior to maturity of a futures contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in futures contract prices. The liquidity of the futures markets depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants make or take delivery, liquidity in the futures market could be reduced. Because of the low margin deposits normally required in futures trading, it is possible that the Fund may employ a high degree of leverage in the portfolio. As a result, a relatively small price movement in a futures contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. For certain types of futures contracts, losses are potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Futures contracts executed (if any) on foreign exchanges may not provide the same protection as U.S. exchanges. Futures contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Derivatives Risk – Inverse Floaters Risk. Inverse variable or floating rate obligations, sometimes referred to as inverse floaters, are a type of over-the-counter derivative debt instrument with a variable or floating coupon rate that moves in the opposite direction of an underlying reference, typically short-term interest rates. While inverse floaters tend to provide more income than similar term and credit quality fixed-rate bonds, they also exhibit greater volatility in price movement, which could result in significant losses for the Fund. An inverse floater may have the effect of investment leverage to the extent that its coupon rate varies by a magnitude that exceeds the magnitude of the change in the index or reference rate of interest, which could result in increased losses for the Fund. Inverse floaters can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Exchange-Traded Fund (ETF) Risk. Investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. ETFs are subject to, among other risks, tracking risk and passive and, in some cases, active investment risk. In addition, shareholders bear both their proportionate share of the Fund’s expenses, and indirectly the ETF’s expenses, incurred through the Fund’s ownership of the ETF. Because the expenses and costs of an underlying ETF are shared by its investors, redemptions by other investors in the ETF could result in decreased economies of scale and increased operating expenses for such ETF. The ETFs may not achieve their investment objective. The Fund, through its investment in ETFs, may not achieve its investment objective.

High-Yield Investments Risk. Securities and other debt instruments held by the Fund that are rated below investment grade (commonly called “high-yield” or “junk” bonds) and unrated debt instruments 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 debt instruments. In addition, these investments have greater price fluctuations, are less liquid and are more likely to experience a default than higher-rated debt instruments. High-yield debt instruments are considered to be predominantly speculative with respect to the issuer’s capacity to pay interest and repay principal.

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 instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, 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. Similarly, a period of rising interest rates may negatively impact the Fund’s performance. Actions by governments and central banking authorities can result in increases in interest rates. Such actions may negatively affect the value of debt instruments held by the Fund, resulting in a negative impact on the Fund's performance and NAV. Any interest rate increases could cause the value of the Fund’s investments in debt instruments to decrease. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses.

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 the underlying funds in direct proportion to the Fund’s investment therein. In addition, investments in ETFs have unique characteristics, including, but not limited to, the expense structure and additional expenses associated with investing in ETFs. The performance of the underlying funds could be adversely affected if other investors 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 an underlying fund are shared by its investors, redemptions by other investors in the underlying funds could result in decreased economies of scale and increased operating expenses for such underlying funds. 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. Also, to the extent that the Fund is constrained/restricted from investing (or investing further) in a particular underlying fund for one or more reasons (e.g., underlying fund capacity constraints or regulatory restrictions) or if the Fund chooses to sell its investment in an underlying fund because of poor investment performance or for other reasons, the Fund may have to invest in other underlying funds, including less desirable funds – from a strategy or investment performance standpoint – which could have a negative impact on Fund performance. In addition, Fund performance could be negatively impacted if an appropriate alternate underlying fund does not present itself in a timely manner or at all. The underlying funds may not achieve their investment objective. The Fund, through its investment in underlying funds, may not achieve its investment objective.

Liquidity Risk. Liquidity risk is the risk associated with any event, circumstance, or characteristic of an investment or market that negatively impacts the Fund’s ability to sell, or realize the proceeds from the sale of, an investment at a desirable time or price. Liquidity risk may arise because of, for example, a lack of marketability of the investment, which means that when seeking to sell its portfolio investments, the Fund could find that selling is more difficult than anticipated, especially during times of high market volatility. Decreases in the number of financial institutions, including banks and broker-dealers, willing to make markets (match up sellers and buyers) in the Fund’s investments or decreases in their capacity or willingness to trade such investments may increase the Fund’s exposure to this risk. The debt market has experienced considerable growth, and financial institutions making markets in instruments purchased and sold by the Fund (e.g., bond dealers) have been subject to increased regulation. The impact of that growth and regulation on the ability and willingness of financial institutions to engage in trading or “making a market” in such instruments remains unsettled. Certain types of investments, such as lower-rated securities or those that are purchased and sold in over-the-counter markets, may be especially subject to liquidity risk. Securities or other assets in which the Fund invests may be traded in the over-the-counter market rather than on an exchange and therefore may be more difficult to purchase or sell at a fair price, which may have a negative impact on the Fund’s performance. Market participants attempting to sell the same or a similar instrument at the same time as the Fund could exacerbate the Fund’s exposure to liquidity risk. The Fund may have to accept a lower selling price for the holding, sell other liquid or more liquid investments that it might otherwise prefer to hold (thereby increasing the proportion of the Fund’s investments in less liquid or illiquid securities), or forego another more appealing investment opportunity. Certain investments that were liquid when purchased by the Fund may later become illiquid, particularly in times of overall economic distress. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity and the price of the Fund's investments. Judgment plays a larger role in valuing illiquid or less liquid investments as compared to valuing liquid or more liquid investments. Price volatility may be higher for illiquid or less liquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to liquid or more liquid investments). Generally, the less liquid the market at the time the Fund sells a portfolio investment, the greater the risk of loss or decline of value to the Fund. Overall market liquidity and other factors can lead to an increase in redemptions, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell investments in a down market. The municipal securities market is an over-the-counter market, which means that the Fund purchases and sells investments through municipal bond dealers. The Fund’s ability to sell investments held in its portfolio is dependent on the willingness and ability of market participants to provide bids that, in the view of portfolio management, reflect current market prices. Adverse market conditions could result in a lack of liquidity by reducing the number of ready buyers.

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 long periods.

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. Certain money market funds float their NAV while others seek to preserve the value of investments at a stable NAV (typically, $1.00 per share). An investment in a money market fund, even an investment in a fund seeking to maintain a stable NAV per share, is not guaranteed and it is possible for the Fund to lose money by investing in these and other types of money market funds. If the liquidity of a money market fund’s portfolio deteriorates below certain levels, the money market fund may suspend redemptions (i.e., impose a redemption gate) and thereby prevent the Fund from selling its investment in the money market fund or impose a fee of up to 2% on amounts the Fund redeems from the money market fund (i.e., impose a liquidity fee). These measures may result in an investment loss or prohibit the Fund from redeeming shares when the Investment Manager would otherwise redeem shares. 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. By investing in a money market fund, the Fund will be exposed to the investment risks of the money market fund in direct proportion to such investment. 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 the Fund’s investments in derivatives. Money market funds and the securities they invest in are subject to comprehensive regulations. The enactment of new legislation or regulations, as well as changes in interpretation and enforcement of current laws, may affect the manner of operation, performance and/or yield of money market funds.

Municipal Securities Risk. Municipal securities are debt obligations generally issued to obtain funds for various public purposes, including general financing for state and local governments, or financing for a specific project or public facility, and include obligations of the governments of the U.S. territories, commonwealths and possessions such as Guam, Puerto Rico and the U.S. Virgin Islands to the extent such obligations are exempt from state and U.S. federal income taxes. The value of municipal securities can be significantly affected by actual or expected political and legislative changes at the federal or state level. Municipal securities may be fully or partially backed by the taxing authority of the local government, by the credit of a private issuer, by the current or anticipated revenues from a specific project or specific assets or by domestic or foreign entities providing credit support, such as letters of credit, guarantees or insurance, and are generally classified into general obligation bonds and special revenue obligations. Because many municipal securities are issued to finance projects in sectors such as education, health care, transportation and utilities, conditions in those sectors can affect the overall municipal market.

Issuers in a state, territory, commonwealth or possession in which the Fund invests may experience significant financial difficulties for various reasons, including as the result of events that cannot be reasonably anticipated or controlled such as social conflict or unrest, labor disruption and natural disasters. Such financial difficulties may lead to credit rating downgrades of such issuers which in turn, could affect the market values and marketability of many or all municipal obligations of issuers in such state, territory, commonwealth or possession. The value of the Fund’s shares will be negatively impacted to the extent it invests in such securities. The Fund’s annual and semiannual reports show the Fund’s investment exposures at a point in time. The risk of investing in the Fund is directly correlated to the Fund’s investment exposures.

Because the Fund invests substantially in municipal securities issued by the state identified in the Fund’s name and political sub-divisions of that state, the Fund will be particularly affected by adverse tax, legislative, regulatory, demographic or political changes as well as changes impacting the state's financial, economic or other condition and prospects. In addition, because of the relatively small number of issuers of tax-exempt securities in the state, the Fund may invest a higher percentage of assets in a single issuer and, therefore, be more exposed to the risk of loss than a fund that invests more broadly. The value of municipal and other securities owned by the Fund also may be adversely affected by future changes in federal or state income tax laws.

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.

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.

Tax Risk. Municipal securities generally pay interest that, in the opinion of bond counsel, is free from U.S. federal income tax (and in some cases, the U.S. federal alternative minimum tax). Income from tax-exempt municipal obligations could be declared taxable, possibly retroactively, because of unfavorable changes in tax laws, adverse interpretations by the Internal Revenue Service, the non-compliant conduct of a bond issuer or under other circumstances. In such event, then the value of the security would likely fall and, as a shareholder of the Fund, you may be required to file an amended tax return and pay additional taxes. For certain bonds issued after December, 2017, the tax-advantaged treatment previously available may be no longer available.

Zero-Coupon Bonds Risk. Zero-coupon bonds are bonds that do not pay interest in cash on a current basis, but instead accrue interest over the life of the bond. As a result, these securities are issued at a discount and their values may fluctuate more than the values of similar securities that pay interest periodically. Although these securities pay no interest to holders prior to maturity, interest accrued on these securities is reported as income to the Fund and affects the amounts distributed to its shareholders, which may cause the Fund to sell investments to obtain cash to make income distributions to shareholders, including at times when it may not be advantageous to do so.
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.
Risk Not Insured Depository Institution [Text] rr_RiskNotInsuredDepositoryInstitution 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.
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Performance Information
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock The following bar chart and table show you how the Fund has performed in the past, and can help you understand the risks of investing in the Fund. The bar chart shows how the Fund’s Class A share performance (without sales charges) has varied for each full calendar year shown. If the sales charges were reflected, returns shown would be lower. The table below the bar chart compares the Fund’s returns (after applicable sales charges shown in the Shareholder Fees table in this prospectus) for the periods shown with a broad measure of market performance, as well as another measure of performance for markets in which the Fund may invest.

The performance of one or more share classes shown in the table below begins before the indicated inception date for such share class. The returns shown for each such share class include the returns of the Fund’s Class A shares (without applicable sales charges and adjusted to reflect the higher class-related operating expenses of such classes, where applicable) for periods prior to its inception date. Except for differences in annual returns resulting from differences in expenses and sales charges (where applicable), the share classes of the Fund would have substantially similar annual returns because all share classes of the Fund invest in the same portfolio of securities.

The after-tax returns shown in the Average Annual Total Returns table below are calculated using the highest historical individual U.S. federal marginal income tax rates in effect during the period indicated in the table and do not reflect the impact of state, local or foreign taxes. Your actual after-tax returns will depend on your personal tax situation and may differ from those shown in the table. In addition, the after-tax returns shown in the table do not apply to shares held in tax-advantaged accounts such as 401(k) plans or Individual Retirement Accounts (IRAs). The after-tax returns are shown only for Class A shares and will vary for other share classes. Returns after taxes on distributions and sale of Fund shares are higher than before-tax returns for certain periods shown because they reflect the tax benefit of capital losses realized on the redemption of Fund shares.

The Fund’s past performance (before and after taxes) is no guarantee of how the Fund will perform in the future. Updated performance information can be obtained by calling toll-free 800.345.6611 or visiting columbiathreadneedle.com/us.
Performance Information Illustrates Variability of Returns [Text] rr_PerformanceInformationIllustratesVariabilityOfReturns The following bar chart and table show you how the Fund has performed in the past, and can help you understand the risks of investing in the Fund. The bar chart shows how the Fund’s Class A share performance (without sales charges) has varied for each full calendar year shown. If the sales charges were reflected, returns shown would be lower. The table below the bar chart compares the Fund’s returns (after applicable sales charges shown in the Shareholder Fees table in this prospectus) for the periods shown with a broad measure of market performance, as well as another measure of performance for markets in which the Fund may invest.
Performance Availability Phone [Text] rr_PerformanceAvailabilityPhone 800.345.6611
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress columbiathreadneedle.com/us
Performance Past Does Not Indicate Future [Text] rr_PerformancePastDoesNotIndicateFuture The Fund’s past performance (before and after taxes) is no guarantee of how the Fund will perform in the future.
Bar Chart [Heading] rr_BarChartHeading Year by Year Total Return (%)
as of December 31 Each Year
Bar Chart Does Not Reflect Sales Loads [Text] rr_BarChartDoesNotReflectSalesLoads The bar chart shows how the Fund’s Class A share performance (without sales charges) has varied for each full calendar year shown. If the sales charges were reflected, returns shown would be lower.
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock Best and Worst Quarterly Returns
During the Period Shown in the Bar Chart

Best                                                          3rd Quarter 2009                                                         9.75%

Worst                                                       4th Quarter 2010                                                        -5.91%
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2017)
Performance Table Does Reflect Sales Loads rr_PerformanceTableDoesReflectSalesLoads The table below the bar chart compares the Fund’s returns (after applicable sales charges shown in the Shareholder Fees table in this prospectus) for the periods shown with a broad measure of market performance, as well as another measure of performance for markets in which the Fund may invest.
Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate The after-tax returns shown in the Average Annual Total Returns table below are calculated using the highest historical individual U.S. federal marginal income tax rates in effect during the period indicated in the table and do not reflect the impact of state, local or foreign taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred In addition, the after-tax returns shown in the table do not apply to shares held in tax-advantaged accounts such as 401(k) plans or Individual Retirement Accounts (IRAs).
Performance Table One Class of after Tax Shown [Text] rr_PerformanceTableOneClassOfAfterTaxShown The after-tax returns are shown only for Class A shares and will vary for other share classes.
Performance Table Explanation after Tax Higher rr_PerformanceTableExplanationAfterTaxHigher Returns after taxes on distributions and sale of Fund shares are higher than before-tax returns for certain periods shown because they reflect the tax benefit of capital losses realized on the redemption of Fund shares.
Columbia Strategic New York Municipal Income Fund | Class A  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases (as a % of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 3.00%
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 0.75% [1]
Management fees rr_ManagementFeesOverAssets 0.47%
Distribution and/or service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other expenses rr_OtherExpensesOverAssets 0.13% [2]
Total annual Fund operating expenses rr_ExpensesOverAssets 0.85%
Less: Fee waivers and/or expense reimbursements rr_FeeWaiverOrReimbursementOverAssets (0.05%) [3]
Total annual Fund operating expenses after fee waivers and/or reimbursements rr_NetExpensesOverAssets 0.80%
Expenses Deferred Charges [Text Block] rr_ExpensesDeferredChargesTextBlock This charge is imposed on certain investments of $500,000 or more redeemed within 12 months after purchase, with certain limited exceptions.
1 year rr_ExpenseExampleYear01 $ 379
3 years rr_ExpenseExampleYear03 558
5 years rr_ExpenseExampleYear05 752
10 years rr_ExpenseExampleYear10 1,313
1 year rr_ExpenseExampleNoRedemptionYear01 379
3 years rr_ExpenseExampleNoRedemptionYear03 558
5 years rr_ExpenseExampleNoRedemptionYear05 752
10 years rr_ExpenseExampleNoRedemptionYear10 $ 1,313
2008 rr_AnnualReturn2008 (8.72%)
2009 rr_AnnualReturn2009 19.57%
2010 rr_AnnualReturn2010 1.37%
2011 rr_AnnualReturn2011 11.92%
2012 rr_AnnualReturn2012 8.73%
2013 rr_AnnualReturn2013 (3.88%)
2014 rr_AnnualReturn2014 10.29%
2015 rr_AnnualReturn2015 3.84%
2016 rr_AnnualReturn2016 0.26%
2017 rr_AnnualReturn2017 5.22%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Best
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Sep. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 9.75%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Worst
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2010
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (5.91%)
1 Year rr_AverageAnnualReturnYear01 2.02%
5 Years rr_AverageAnnualReturnYear05 2.41%
10 Years rr_AverageAnnualReturnYear10 4.25%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Sep. 26, 1986
Columbia Strategic New York Municipal Income Fund | Class Adv  
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 0.47%
Distribution and/or service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.13% [2]
Total annual Fund operating expenses rr_ExpensesOverAssets 0.60%
Less: Fee waivers and/or expense reimbursements rr_FeeWaiverOrReimbursementOverAssets (0.05%) [3]
Total annual Fund operating expenses after fee waivers and/or reimbursements rr_NetExpensesOverAssets 0.55%
1 year rr_ExpenseExampleYear01 $ 56
3 years rr_ExpenseExampleYear03 187
5 years rr_ExpenseExampleYear05 330
10 years rr_ExpenseExampleYear10 745
1 year rr_ExpenseExampleNoRedemptionYear01 56
3 years rr_ExpenseExampleNoRedemptionYear03 187
5 years rr_ExpenseExampleNoRedemptionYear05 330
10 years rr_ExpenseExampleNoRedemptionYear10 $ 745
1 Year rr_AverageAnnualReturnYear01 5.49%
5 Years rr_AverageAnnualReturnYear05 3.28%
10 Years rr_AverageAnnualReturnYear10 4.70%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Mar. 19, 2013
Columbia Strategic New York Municipal Income 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% [4]
Management fees rr_ManagementFeesOverAssets 0.47%
Distribution and/or service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other expenses rr_OtherExpensesOverAssets 0.13% [2]
Total annual Fund operating expenses rr_ExpensesOverAssets 1.60%
Less: Fee waivers and/or expense reimbursements rr_FeeWaiverOrReimbursementOverAssets (0.05%) [3]
Total annual Fund operating expenses after fee waivers and/or reimbursements rr_NetExpensesOverAssets 1.55%
Expenses Deferred Charges [Text Block] rr_ExpensesDeferredChargesTextBlock This charge applies to redemptions within 12 months after purchase, with certain limited exceptions.
1 year rr_ExpenseExampleYear01 $ 258
3 years rr_ExpenseExampleYear03 500
5 years rr_ExpenseExampleYear05 866
10 years rr_ExpenseExampleYear10 1,896
1 year rr_ExpenseExampleNoRedemptionYear01 158
3 years rr_ExpenseExampleNoRedemptionYear03 500
5 years rr_ExpenseExampleNoRedemptionYear05 866
10 years rr_ExpenseExampleNoRedemptionYear10 $ 1,896
1 Year rr_AverageAnnualReturnYear01 3.61%
5 Years rr_AverageAnnualReturnYear05 2.57%
10 Years rr_AverageAnnualReturnYear10 4.09%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Aug. 01, 1997
Columbia Strategic New York Municipal Income Fund | Class Inst  
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 0.47%
Distribution and/or service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.13% [2]
Total annual Fund operating expenses rr_ExpensesOverAssets 0.60%
Less: Fee waivers and/or expense reimbursements rr_FeeWaiverOrReimbursementOverAssets (0.05%) [3]
Total annual Fund operating expenses after fee waivers and/or reimbursements rr_NetExpensesOverAssets 0.55%
1 year rr_ExpenseExampleYear01 $ 56
3 years rr_ExpenseExampleYear03 187
5 years rr_ExpenseExampleYear05 330
10 years rr_ExpenseExampleYear10 745
1 year rr_ExpenseExampleNoRedemptionYear01 56
3 years rr_ExpenseExampleNoRedemptionYear03 187
5 years rr_ExpenseExampleNoRedemptionYear05 330
10 years rr_ExpenseExampleNoRedemptionYear10 $ 745
1 Year rr_AverageAnnualReturnYear01 5.49%
5 Years rr_AverageAnnualReturnYear05 3.29%
10 Years rr_AverageAnnualReturnYear10 4.72%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Sep. 01, 2011
Columbia Strategic New York Municipal Income Fund | Class Inst2  
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 0.47%
Distribution and/or service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.12% [2]
Total annual Fund operating expenses rr_ExpensesOverAssets 0.59%
Less: Fee waivers and/or expense reimbursements rr_FeeWaiverOrReimbursementOverAssets (0.05%) [3]
Total annual Fund operating expenses after fee waivers and/or reimbursements rr_NetExpensesOverAssets 0.54%
1 year rr_ExpenseExampleYear01 $ 55
3 years rr_ExpenseExampleYear03 184
5 years rr_ExpenseExampleYear05 324
10 years rr_ExpenseExampleYear10 733
1 year rr_ExpenseExampleNoRedemptionYear01 55
3 years rr_ExpenseExampleNoRedemptionYear03 184
5 years rr_ExpenseExampleNoRedemptionYear05 324
10 years rr_ExpenseExampleNoRedemptionYear10 $ 733
1 Year rr_AverageAnnualReturnYear01 5.49%
5 Years rr_AverageAnnualReturnYear05 3.30%
10 Years rr_AverageAnnualReturnYear10 4.71%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Nov. 08, 2012
Columbia Strategic New York Municipal Income Fund | Class Inst3  
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 0.47%
Distribution and/or service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.08% [2]
Total annual Fund operating expenses rr_ExpensesOverAssets 0.55%
Less: Fee waivers and/or expense reimbursements rr_FeeWaiverOrReimbursementOverAssets (0.05%) [3]
Total annual Fund operating expenses after fee waivers and/or reimbursements rr_NetExpensesOverAssets 0.50%
1 year rr_ExpenseExampleYear01 $ 51
3 years rr_ExpenseExampleYear03 171
5 years rr_ExpenseExampleYear05 302
10 years rr_ExpenseExampleYear10 684
1 year rr_ExpenseExampleNoRedemptionYear01 51
3 years rr_ExpenseExampleNoRedemptionYear03 171
5 years rr_ExpenseExampleNoRedemptionYear05 302
10 years rr_ExpenseExampleNoRedemptionYear10 $ 684
1 Year rr_AverageAnnualReturnYear01 5.33%
5 Years rr_AverageAnnualReturnYear05 3.06%
10 Years rr_AverageAnnualReturnYear10 4.58%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Mar. 01, 2017
Columbia Strategic New York Municipal Income Fund | returns after taxes on distributions | Class A  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 1.97%
5 Years rr_AverageAnnualReturnYear05 2.35%
10 Years rr_AverageAnnualReturnYear10 4.14%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Sep. 26, 1986
Columbia Strategic New York Municipal Income Fund | returns after taxes on distributions and sale of Fund shares | Class A  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 2.54%
5 Years rr_AverageAnnualReturnYear05 2.61%
10 Years rr_AverageAnnualReturnYear10 4.16%
Share Class Inception Date rr_AverageAnnualReturnInceptionDate Sep. 26, 1986
Columbia Strategic New York Municipal Income Fund | Bloomberg Barclays New York Municipal Bond Index (reflects no deductions for fees, expenses or taxes)  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 5.09%
5 Years rr_AverageAnnualReturnYear05 3.01%
10 Years rr_AverageAnnualReturnYear10 4.38%
Columbia Strategic New York Municipal Income Fund | Bloomberg Barclays Municipal Bond Index (reflects no deductions for fees, expenses or taxes)  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 5.45%
5 Years rr_AverageAnnualReturnYear05 3.02%
10 Years rr_AverageAnnualReturnYear10 4.46%
[1] This charge is imposed on certain investments of $500,000 or more redeemed within 12 months after purchase, with certain limited exceptions.
[2] Other expenses have been restated to reflect current transfer agency fees paid by the Fund and other expenses for Class Inst3 shares are based on estimated amounts for the Fund’s current fiscal year.
[3] Columbia Management Investment Advisers, LLC and certain of its affiliates have contractually agreed to waive fees and/or to reimburse expenses (excluding transaction costs and certain other investment related expenses, interest, taxes, acquired fund fees and expenses, and infrequent and/or unusual expenses) through February 28, 2019, 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 0.80% for Class A, 0.55% for Class Adv, 1.55% for Class C, 0.55% for Class Inst, 0.54% for Class Inst2 and 0.50% for Class Inst3.
[4] This charge applies to redemptions within 12 months after purchase, with certain limited exceptions.