Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	AIM INVESTMENT SECURITIES FUNDS (INVESCO INVESTMENT SECURITIES FUNDS)
Prospectus Date	rr_ProspectusDate	Jun. 28, 2012
Class Institutional | Invesco Global Real Estate Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summaries - INVESCO GLOBAL REAL ESTATE FUND
Objective [Heading]	rr_ObjectiveHeading	Investment Objective(s)
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Fund’s investment objective is total return through growth of capital and current income.
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.
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)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover.
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 54% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	54.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	Example.
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.           The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.           Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies of the Fund
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in securities of real estate and real estate-related issuers. The Fund invests primarily in equity securities but may also invest in debt securities including U.S. Treasury and agency bonds and notes.            In complying with the 80% investment requirement, the Fund may include synthetic securities that have economic characteristics similar to the Fund’s direct investments that are counted toward the 80% investment requirement.           The Fund considers an issuer to be a real estate or real estate-related issuer if at least 50% of its assets, gross income or net profits are attributable to ownership, construction, management or sale of residential, commercial or industrial real estate. These companies include (i) real estate investment trusts (REITs) or other real estate operating companies that (a) own property, (b) make or invest in short term construction and development mortgage loans, or (c) invest in long-term mortgages or mortgage pools, and (ii) companies whose products and services are related to the real estate industry, such as manufacturers and distributors of building supplies and financial institutions that issue or service mortgages.           The Fund may invest in equity and debt securities of companies unrelated to the real estate industry that the portfolio managers believe are undervalued and have potential for growth of capital. The Fund limits its investments in debt securities unrelated to the real estate industry to those that are investment-grade or deemed by the Fund’s portfolio managers to be of comparable quality.           The Fund invests, under normal circumstances, in issuers located in at least three different countries, including the U.S. As of February 29, 2012, the principal countries in which the Fund invested were the United States, Hong Kong, Japan, Australia and the United Kingdom.           The Fund may invest in non-investment grade debt securities (commonly known as “junk bonds”) of real estate and real estate-related issuers.           The Fund may engage in short sales of securities. A short sale occurs when the Fund sells a security, but does not deliver a security it owns when the sale settles. Instead, it borrows that security for delivery when the sale settles. The Fund may engage in short sales with respect to securities it owns (short sales against the box) or securities it does not own. Generally, the Fund will sell a security short to (1) take advantage of an expected decline in the security price in anticipation of purchasing the same security at a later date at a lower price, or (2) to protect a profit in a security that it owns (short sales against the box). The Fund will not sell a security short if, as a result of such short sale, the aggregate market value of all securities sold short exceeds 10% of the Fund’s net assets.           When constructing the portfolio, the portfolio managers use a fundamentals-driven investment process, including an evaluation of factors such as real property market cycle analysis, real property evaluation and management and structure review to identify securities with characteristics including (i) quality underlying properties, (ii) solid management teams with the ability to effectively manage capital structure decisions, and (iii) attractive valuations relative to peer investment alternatives. The portfolio managers and investment team focus on equity REITs and real estate operating issuers. Some of the fundamental factors that are evaluated in screening potential investments for the Fund include: forecasted occupancy and rental rates of the various property markets in which a firm may operate, property locations, physical attributes and cash flow generating capacity of an issuer’s properties and calculating relative return potential, asset quality, management depth and skill, insider ownership, overall debt levels, percentage of variable rate financing and fixed charge coverage ratios. The issuers that are believed to have the most attractive fundamental attributes are then screened according to pricing factors that allow the management team to assess security valuations relative to one another and relative to the investment teams’ assessment of underlying asset value. The portfolio managers also consider the relative liquidity of each security in the construction of the Fund. The portfolio managers seek to construct a portfolio with risk characteristics similar to the FTSE EPRA/NAREIT Developed Real Estate Index (the benchmark index). The Fund seeks to limit risk through various controls, such as diversifying the portfolio property types and geographic areas as well as by limiting the size of any one holding. Various factors may lead to overweighting or underweighting of particular property types and/or geographic areas from time to time.           The portfolio managers will consider selling a security if they conclude (1) its relative valuation falls below desired levels, (2) its risk/return profile changes significantly, (3) its fundamentals change, or (4) a more attractive investment opportunity is identified.
Risk [Heading]	rr_RiskHeading	Principal Risks of Investing in the Fund
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	As with any mutual fund investment, loss of money is a risk of investing. 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 risks associated with an investment in the Fund can increase during times of significant market volatility. The principal risks of investing in the Fund are:           Concentration Risk. To the extent the Fund invests a greater amount in any one sector or industry, the Fund’s performance will depend to a greater extent on the overall condition of the sector or industry, and there is increased risk to the Fund if conditions adversely affect that sector or industry.           Credit Risk. The issuer of instruments in which the Fund invests may be unable to meet interest and/or principal payments, thereby causing its instruments to decrease in value and lowering the issuer’s credit rating.           Foreign Securities Risk. The Fund’s foreign investments may be affected by changes in a foreign country’s exchange rates, political and social instability, changes in economic or taxation policies, difficulties when enforcing obligations, decreased liquidity, and increased volatility. Foreign companies may be subject to less regulation resulting in less publicly available information about the companies.           High Yield Bond (Junk Bond) Risk. Junk bonds involve a greater risk of default or price changes due to changes in the credit quality of the issuer. The values of junk bonds fluctuate more than those of high-quality bonds in response to company, political, regulatory or economic developments. Values of junk bonds can decline significantly over short periods of time.           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 their individual characteristics, including duration.           Management Risk. The investment techniques and risk analysis used by the Fund’s portfolio managers may not produce the desired results.           Market Risk. The prices of and the income generated by the Fund’s securities may decline in response to, among other things, investor sentiment, general economic and market conditions, regional or global instability, and currency and interest rate fluctuations.           REIT Risk/Real Estate Risk. Investments in real estate related instruments may be affected by economic, legal, cultural, environmental or technological factors that affect property values, rents or occupancies of real estate related to the Fund’s holdings. Real estate companies, including REITs or similar structures, tend to be small and mid cap companies, and their shares may be more volatile and less liquid. The value of investments in real estate related companies may be affected by the quality of management, the ability to repay loans, the utilization of leverage and financial covenants related thereto, whether the company carries adequate insurance and environmental factors. If a real estate related company defaults, the Fund may own real estate directly, which involves the following additional risks: environmental liabilities, difficulty in valuing and selling the real estate, and economic or regulatory changes.           Short Sales Risk. Short sales may cause the Fund to repurchase a security at a higher price, causing a loss. As there is no limit on how much the price of the security can increase, the Fund’s exposure is unlimited.           Synthetic Securities Risk. Fluctuations in the values of synthetic securities may not correlate perfectly with the instruments they are designed to replicate. Synthetic securities may be subject to interest rate changes, market price fluctuations, counterparty risk and liquidity risk.           U.S. Government Obligations Risk. The Fund may invest in obligations issued by U.S. Government agencies and instrumentalities that may receive varying levels of support from the government, which could affect the Fund’s ability to recover should they default.
Risk Lose Money [Text]	rr_RiskLoseMoney	As with any mutual fund investment, loss of money is a risk of investing.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	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.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance Information
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and performance table provide an indication of the risks of investing in the Fund. The bar chart shows changes in the performance of the Fund from year to year as of December 31. The performance table compares the Fund’s performance to that of a broad-based securities market benchmark, a style specific benchmark and a peer group benchmark comprised of funds with investment objectives and strategies similar to the Fund. The Fund’s past performance (before and after taxes) is not necessarily an indication of its future performance. Updated performance information is available on the Fund’s website at www.invesco.com/us.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and performance table provide an indication of the risks of investing in the Fund. The bar chart shows changes in the performance of the Fund from year to year as of December 31. The performance table compares the Fund’s performance to that of a broad-based securities market benchmark, a style specific benchmark and a peer group benchmark comprised of funds with investment objectives and strategies similar to the Fund.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.invesco.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund’s past performance (before and after taxes) is not necessarily an indication of its future performance.
Bar Chart [Heading]	rr_BarChartHeading	Annual Total Returns
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Institutional Class shares year-to-date (ended March 31, 2012): 12.54% Best Quarter (ended June 30, 2009): 29.88% Worst Quarter (ended December 31, 2008): -29.37%
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (for the periods ended December 31, 2011)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangement, such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangement, such as 401(k) plans or individual retirement accounts.
Class Institutional | Invesco Global Real Estate Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)	rr_MaximumDeferredSalesChargeOverOther	none
Management Fees	rr_ManagementFeesOverAssets	0.74%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.17%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.91%
1 Year	rr_ExpenseExampleYear01	93
3 Years	rr_ExpenseExampleYear03	290
5 Years	rr_ExpenseExampleYear05	504
10 Years	rr_ExpenseExampleYear10	1,120
2006	rr_AnnualReturn2006	41.37%
2007	rr_AnnualReturn2007	(5.10%)
2008	rr_AnnualReturn2008	(44.68%)
2009	rr_AnnualReturn2009	31.32%
2010	rr_AnnualReturn2010	17.69%
2011	rr_AnnualReturn2011	(6.51%)
Year to Date Return, Label	rr_YearToDateReturnLabel	Institutional Class shares year-to-date
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Mar. 31, 2012
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	12.54%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	29.88%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(29.37%)
1 Year	rr_AverageAnnualReturnYear01	(6.51%)
5 Years	rr_AverageAnnualReturnYear05	(5.38%)
Since Inception	rr_AverageAnnualReturnSinceInception	3.57%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 29, 2005
Class Institutional | Return After Taxes on Distributions | Invesco Global Real Estate Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(7.09%)
5 Years	rr_AverageAnnualReturnYear05	(6.63%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.22%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 29, 2005
Class Institutional | Return After Taxes on Distributions and Sale of Fund Shares | Invesco Global Real Estate Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(4.08%)
5 Years	rr_AverageAnnualReturnYear05	(5.05%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.42%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 29, 2005
Class Institutional | MSCI World Index: from (4/30/2005) | Invesco Global Real Estate Fund
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(5.54%)
5 Years	rr_AverageAnnualReturnYear05	(2.37%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.84%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 2005
Class Institutional | FTSE EPRA/NAREIT Developed Real Estate Index: from (4/30/2005) (reflects no deduction for fees, expenses or taxes) | Invesco Global Real Estate Fund
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(5.82%)
5 Years	rr_AverageAnnualReturnYear05	(5.28%)
Since Inception	rr_AverageAnnualReturnSinceInception	3.72%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 2005
Class Institutional | Lipper Global Real Estate Funds Category Average: from (4/30/2005) | Invesco Global Real Estate Fund
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(6.90%)
5 Years	rr_AverageAnnualReturnYear05	(6.13%)
Since Inception	rr_AverageAnnualReturnSinceInception	2.28%
Inception Date	rr_AverageAnnualReturnInceptionDate	Apr. 30, 2005