Series and Index [Domain]
AIM Tax-Exempt Cash Fund
Share Class [Domain]
Class A Investor Class
Prospectus [Line Items]
Risk Return [Abstract]
Risk Return [Heading] Risk/Return Summary
Objective Section [Abstract]
Objective Primary [Text Block] The fund's investment objective is to provide as high a level of tax-exempt income as is consistent with the preservation of capital and maintenance of liquidity.
The fund's investment objective may be changed by the Board of Trustees without shareholder approval.
Expenses [Abstract]
Expense [Heading] Fee Table and Expense Example
Expense Narrative [Text Block] If a financial institution is managing your account, you may also be charged a transaction or other fee by such financial institution.
As a result of 12b-1 fees, long-term shareholders in the fund may pay more than the maximum permitted initial sales charge.
Shareholder Fees [Abstract]
Shareholder Fees Caption Shareholder Fees
(fees paid directly from your investment)
Maximum Sales Charge Imposed on Purchases over Offering Price 0% 0%
Maximum Deferred Sales Charge over Offering Price 0% 0%
Operating Expenses [Abstract]
Operating Expenses Caption Annual Fund Operating Expense
Net Expenses over Assets [Abstract]
Expenses over Assets [Abstract]
Management Fees over Assets 0.35% 0.35%
Distribution and Service (12b-1) Fees over Assets 0.25% 0%
Other Expenses over Assets [Abstract]
Other Expenses over Assets 0.59% 0.59%
Acquired Fund Fees and Expenses over Assets 0% 0%
Expenses over Assets 1.19% 0.94%
Fee Waiver or Reimbursement over Assets (0.15%) 0%
Net Expenses over Assets 1.04% 0.94%
Expense Example Narrative [Abstract]
Expense Example [Heading] EXPENSE EXAMPLE
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in different classes the fund with the cost of investing in other mutual funds.
The expense example assumes you:
(i) invest $10,000 in the fund for the time periods indicated;
(ii) redeem all of your shares at the end of the periods indicated;
(iii) earn a 5% return on your investment before operating expenses each year; and
(iv) incur the same amount in operating expenses each year (after giving effect to any applicable contractual fee waivers and/or expense reimbursements).
To the extent fees are waived and/or expenses are reimbursed voluntarily, your expenses will be lower. Although your actual returns and costs may be higher or lower, based on these assumptions your costs would be:
Expense Example by Year Caption Class A Investor Class
Expense Example [Abstract]
Expense Example Year 01 106 96
Expense Example Year 03 363 300
Expense Example Year 05 640 520
Expense Example Year 10 1,430 1,155
Strategy Section [Abstract]
Strategy [Heading] OBJECTIVE AND STRATEGIES
Strategy Narrative [Text Block] The fund normally invests at least 80% of its assets in debt securities that (1) pay interest that is excluded from gross income for federal income tax purposes, and (2) do not produce income that will be considered to be an item of preference for purposes of the alternative minimum tax.
The fund invests in accordance with industry-standard requirements for money market funds for the quality, maturity and diversification of investments.
The fund invests only in high-quality U.S. dollar-denominated short term debt obligations, including: (i) municipal securities, which may include tax-exempt commercial paper; and (ii) cash equivalents. These securities may have credit and liquidity enhancements provided by banks, insurance companies or other financial institutions.
Municipal securities include debt obligations of states, territories and possessions of the United States and the District of Columbia, their political subdivisions, agencies, and instrumentalities, authorities thereof, and multi-state agencies, issued to obtain funds for various public purposes. Synthetic municipal securities, which include variable rate instruments that are created when fixed rate bonds are coupled with a third party tender feature and variable tender fees are treated as municipal securities. Other securities held by the fund may be structured with demand features which have the effect of shortening the security's maturity.
The fund invests only in municipal securities that are: (1) rated in the highest rating category by two nationally recognized statistical rating organizations (NRSRO); (2) rated by only one NRSRO, if they are rated in the highest category by that NRSRO; and (3) unrated but deemed to be of comparable quality by the advisors.
Some of the fund's investments, although U.S. dollar-denominated, may be subject to foreign credit exposure.
The fund may invest up to 20% of its net assets in money market instruments that may be subject to federal taxes, including Treasury securities, repurchase agreements, bankers' acceptances, commercial paper, U.S. dollar-denominated foreign securities and master notes.
The fund's investments in the types of securities described in this prospectus vary from time to time, and, at any time, the fund may not be invested in all types of securities described in this prospectus. Any percentage limitations with respect to assets of the fund are applied at the time of purchase.
In selecting securities for the fund's portfolio, the portfolio managers focus on safety, liquidity, and yield that is exempt from federal income taxes. The portfolio structure is driven to some extent by the supply and availability of municipal obligations. The portfolio managers manage liquidity with daily and weekly variable-rate demand notes.
The portfolio managers consider selling a security: (i) if the issuer's credit quality declines, (ii) if a geographic region in which the issuer's in which the fund invests are located undergoes a negative change, (iii) as a result of interest rate changes, or (iv) to enhance yield.
The fund may maintain a portion of its assets in cash pending investment or to handle its daily cash needs, including payment of fund expenses, redemption requests and securities transactions. Depending upon the then-current investment environment, holding a relatively larger percentage of portfolio assets in cash may either assist or hinder the fund's relative performance.
Risk Section [Abstract]
Risk [Heading] RISKS
Risk Lose Money Although the fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the fund.
Risk Money Market Fund Although the fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the fund.
Risk Not Insured Depository Institution An investment in the fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.
Risk Narrative [Text Block] Although the fund seeks to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the fund.

Additionally, the fund's yield will vary as the short-term securities in its portfolio mature or are sold, and the proceeds are reinvested in securities with different interest rates.

An investment in the fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

The principal risks of investing in the fund are:

- Market Risk - The prices of and the income generated by securities held by the fund may decline in response to certain events, including those directly involving the issuers, or in the case of industrial development revenue bonds, the company for whose benefit the bonds are being issued; general economic and market conditions; regional or global economic instability; and interest rate fluctuations.

- Money Market Fund Risk - The fund is a money market fund and an investment in the fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Although the fund seeks to preserve the value of an investment at $1.00 per share, it is possible to lose money by investing in the fund. Additionally, the fund's yield will vary as the short-term securities in its portfolio mature and the proceeds are reinvested in other securities.

- Interest Rate Risk - Interest rate risk refers to the risk that bond prices generally fall as interest rates rise; conversely, bond prices generally rise as interest rates fall. Specific bonds differ in their sensitivity to changes in interest rates depending on specific characteristics of each bond.

- Credit Risk - There is a possibility that the issuers of instruments in which the fund invests will be unable to meet interest payments or repay principal. Changes in the financial strength of an issuer may reduce the credit rating of its securities and may decrease their value. Changes in the credit quality of financial institutions providing liquidity and credit enhancements could cause the fund to experience a loss and may effect its share price.
- Municipal Securities Risk - The value of, payment of interest and repayment of principal with respect to, and the ability of the fund to sell, a municipal security may be affected by constitutional amendments, legislative enactments, executive orders, administrative regulations and voter initiatives as well as the economics of the regions in which the issuers in which the fund invests are located. Revenue bonds are generally not backed by the taxing power of the issuing municipality. To the extent that a municipal security in which the fund invests is not heavily followed by the investment community or such security issue is relatively small, the security may be difficult to value or sell at a fair price.

- Concentration Risk - Because many municipal securities are issued to finance similar projects, especially those relating to education, health care, transportation and utilities, conditions in those sectors can affect the overall municipal securities market and the fund. Moreover, sizeable investments in securities issued to finance similar projects could involve an increased risk to the fund if economic or other factors adversely affect the viability of these projects.

- Foreign Credit Exposure Risk - U.S. dollar-denominated securities which carry foreign credit exposure may be affected by unfavorable political, economic or governmental developments that could affect the repayment of principal or the payment of interest.

- Synthetic Municipal Securities Risk - The tax-exempt character of the interest paid on synthetic municipal securities is based on the tax-exempt income stream from the collateral. The Internal Revenue Service has not ruled on this issue and could deem income derived from synthetic municipal securities to be taxable.

- Management Risk - There is no guarantee that the investment techniques and risk analyses used by the fund's portfolio manager(s) will produce the desired results.
Bar Chart and Performance Table Section [Abstract]
Bar Chart and Performance Table [Heading] Performance Information
Performance Past Does Not Indicate Future The fund's past performance is not necessarily an indication of its future performance.
Performance Narrative [Text Block] The bar chart and table shown below provide an indication of the risks of investing in the fund.
The fund's past performance is not necessarily an indication of its future performance.
Bar Chart Narrative [Abstract]
Bar Chart [Heading] ANNUAL TOTAL RETURNS
Bar Chart Does Not Reflect Sales Loads Class A shares of the fund are not subject to sales loads.
Bar Chart Narrative [Text Block] The following bar chart shows changes in the performance of the fund's Class A shares from year to year.
Class A shares of the fund are not subject to sales loads.
Bar Chart Table [Abstract]
Annual Return 1997 3.08%
Annual Return 1998 2.99%
Annual Return 1999 2.87%
Annual Return 2000 3.8%
Annual Return 2001 2.38%
Annual Return 2002 0.87%
Annual Return 2003 0.47%
Annual Return 2004 0.54%
Annual Return 2005 1.6%
Annual Return 2006 2.52%
Bar Chart Closing [Abstract]
Year to Date Return Label year-to-date total return
Bar Chart Year to Date Return 1.4%
Bar Chart Year to Date Return Date 2007-06-30
Highest Quarterly Return Label highest quarterly return
Bar Chart Highest Quarterly Return 1%
Bar Chart Highest Quarterly Return Date 2000-12-31
Lowest Quarterly Return Label lowest quarterly return
Bar Chart Lowest Quarterly Return 0.08%
Bar Chart Lowest Quarterly Return Date 2003-09-30
Performance Narrative [Abstract]
Performance Table [Heading] PERFORMANCE TABLE
Performance Table Narrative [Text Block] The bar chart and table shown below provide an indication of the risks of investing in the fund.
The fund's past performance is not necessarily an indication of its future performance.
The following performance table reflects the fund's performance over the periods indicated.
Average Annual Return Caption Average Annual Total Returns (for the periods ended December31, 2006)
Performance Table Section [Abstract]
Average Annual Return [Abstract]
Average Annual Return Label Class A Investor Class
Average Annual Return Year 01 2.52% 2.62%
Average Annual Return Year 05 1.2% 1.26%
Average Annual Return Year 10 2.11% 2.14%
Average Annual Return Inception Date 1982-09-22 1982-09-22
Money Market Seven Day Yield Caption seven-day yield
December 31, 2006
Money Market Seven Day Yield Phone (800) 959-4246
Money Market Seven Day Yield 2.88% 2.98%