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N-2 - USD ($) | 3 Months Ended | 12 Months Ended |
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Oct. 31, 2023 | Jul. 31, 2023 | Apr. 30, 2023 | Jan. 31, 2023 | Oct. 31, 2022 | Jul. 31, 2022 | Apr. 30, 2022 | Jan. 31, 2022 | Oct. 31, 2021 | Jul. 31, 2021 | Apr. 30, 2021 | Jan. 31, 2021 | Oct. 31, 2023 | Oct. 31, 2022 | Oct. 31, 2021 | Oct. 31, 2020 | Oct. 31, 2019 | Oct. 31, 2018 | Oct. 31, 2017 | Oct. 31, 2016 | Oct. 31, 2015 | Oct. 31, 2014 | Oct. 31, 2013
Cover [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Entity Central Index Key |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0001171471 |  |  |  |  |  |  |  |  |  |  |  |
Amendment Flag |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | false |  |  |  |  |  |  |  |  |  |  |  |
Document Type |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | N-CSR |  |  |  |  |  |  |  |  |  |  |  |
Entity Registrant Name |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Calamos Convertible Opportunities and Income Fund |  |  |  |  |  |  |  |  |  |  |  |
Document Period End Date |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Oct. 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |
Fee Table [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shareholder Transaction Expenses [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SHAREHOLDER TRANSACTION EXPENSES |
Sales Load (as a percentage of offering price) |  |  | — | (1)​ |
Offering Expenses Borne by the Fund (as a percentage of offering price) |  |  | — | (1)​ |
Dividend Reinvestment Plan Fees (per sales transaction fee)(2)​ |  | $ | 15.00 |  |
(1) ​If the securities to which this prospectus relates are sold to or through underwriters, the prospectus supplement will set forth any applicable sales load and the estimated offering expenses borne by us. (2) ​Shareholders will pay a $15.00 transaction fee plus a $0.02 per share brokerage charge if they direct the Plan Agent (as defined below) to sell common shares held in a Plan account. In addition, each participant will pay a pro rata share of brokerage commissions incurred with respect to the Plan Agent's open-market purchases in connection with the reinvestment of dividends or distributions. If a participant elects to have the Plan Agent sell part or all of his or her common shares and remit the proceeds, such participant will be charged his or her pro rata share of brokerage commissions on the shares sold. See "Dividends and Distributions on Common Shares; Automatic Dividend Reinvestment Plan". |  |  |  |  |  |  |  |  |  |  |  |
Sales Load [Percent] | [1] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% |  |  |  |  |  |  |  |  |  |  |  |
Dividend Reinvestment and Cash Purchase Fees | [2] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15 |  |  |  |  |  |  |  |  |  |  |  |
Other Transaction Expenses [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Transaction Expenses [Percent] | [1] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% |  |  |  |  |  |  |  |  |  |  |  |
Annual Expenses [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
ANNUAL EXPENSES |  | PERCENTAGE OF AVERAGE NET ASSETS ATTRIBUTABLE TO COMMON SHAREHOLDERS |
Management Fee(3)​ |  |  | 1.29 | % |
Interest Payments on Borrowed Funds(4)​ |  |  | 2.39 | % |
Preferred Stock Dividend Payments(5)​ |  |  | 0.62 | % |
Other Expenses(6)​ |  |  | 0.10 | % |
Total Annual Expenses |  |  | 4.40 | % |
(3) ​The Fund pays Calamos an annual management fee, payable monthly in arrears, for its investment management services in an amount equal to 0.80% of the Fund's average weekly managed assets. In accordance with the requirements of the Commission, the table above shows the Fund's management fee as a percentage of average net assets attributable to common shareholders. By showing the management fee as a percentage of net assets, the management fee is not expressed as a percentage of all of the assets the Fund intends to invest. For purposes of the table, the management fee has been converted to 1.29% of the Fund's average weekly net assets as of October 31, 2023 by dividing the total dollar amount of the management fee by the Fund's average weekly net assets (managed assets less outstanding leverage). (4) ​Reflects interest expense paid on $240 million in average borrowings under the SSB Agreement, plus $83 million in additional average structural leverage related to certain securities lending programs, as described under "Leverage". (5) ​Reflects estimated dividend expense on $133 million aggregate liquidation preference of mandatory redeemable preferred shares outstanding. See "Leverage". (6) ​"Other Expenses" are based on estimated amounts for the Fund's current fiscal year. |  |  |  |  |  |  |  |  |  |  |  |
Management Fees [Percent] | [3] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.29% |  |  |  |  |  |  |  |  |  |  |  |
Interest Expenses on Borrowings [Percent] | [4] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.39% |  |  |  |  |  |  |  |  |  |  |  |
Dividend Expenses on Preferred Shares [Percent] | [5] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.62% |  |  |  |  |  |  |  |  |  |  |  |
Other Annual Expenses [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Annual Expenses [Percent] | [6] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.10% |  |  |  |  |  |  |  |  |  |  |  |
Total Annual Expenses [Percent] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.40% |  |  |  |  |  |  |  |  |  |  |  |
Expense Example [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The following example illustrates the expenses that common shareholders would pay on a $1,000 investment in common shares, assuming (1) total annual expenses of 4.40% of net assets attributable to common shareholders; (2) a 5% annual return; and (3) all distributions are reinvested at net asset value:
|  | 1 YEAR |  | 3 YEARS |  | 5 YEARS |  | 10 YEARS |
Total Expenses Paid by Common Shareholders(7)​ |  | $ | 44 |  |  | $ | 133 |  |  | $ | 223 |  |  | $ | 453 |  |
(7)​ The example does not include sales load or estimated offering costs, which would cause the expenses shown in the example to increase. In connection with an offering of common shares, the applicable prospectus supplement will set forth an example including sales load and estimated offering costs. |  |  |  |  |  |  |  |  |  |  |  |
Expense Example, Year 01 | [7] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 44 |  |  |  |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 3 | [7] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 133 |  |  |  |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 5 | [7] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 223 |  |  |  |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 10 | [7] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 453 |  |  |  |  |  |  |  |  |  |  |  |
Purpose of Fee Table , Note [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The following table and example contain information about the costs and expenses that common shareholders will bear directly or indirectly. In accordance with Commission requirements, the table below shows our expenses, including interest payments on borrowed funds, and preferred stock dividend payments, as a percentage of our average net assets as of October 31, 2023, and not as a percentage of gross assets or managed assets. By showing expenses as a percentage of average net assets, expenses are not expressed as a percentage of all of the assets we invest. The table and example are based on our capital structure as of October 31, 2023. As of October 31, 2023, the Fund had utilized $314 million of the $430 million available under the SSB Agreement ($260 million in advances outstanding, and $54 million in structural leverage consisting of collateral received from counterparties via SSB in connection with securities on loan), representing 28.1% of the Fund's managed assets as of that date, and had $133 million in MRPS outstanding, representing 11.9% of the Fund's managed assets. Combined, the borrowings under the SSB Agreement and the outstanding MRPS represented 39.9% of the Fund's managed assets. |  |  |  |  |  |  |  |  |  |  |  |
Basis of Transaction Fees, Note [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | as a percentage of offering price |  |  |  |  |  |  |  |  |  |  |  |
Other Expenses, Note [Text Block] | [7] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | "Other Expenses" are based on estimated amounts for the Fund's current fiscal year. |  |  |  |  |  |  |  |  |  |  |  |
Management Fee not based on Net Assets, Note [Text Block] | [7] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The Fund pays Calamos an annual management fee, payable monthly in arrears, for its investment management services in an amount equal to 0.80% of the Fund's average weekly managed assets. In accordance with the requirements of the Commission, the table above shows the Fund's management fee as a percentage of average net assets attributable to common shareholders. By showing the management fee as a percentage of net assets, the management fee is not expressed as a percentage of all of the assets the Fund intends to invest. For purposes of the table, the management fee has been converted to 1.29% of the Fund's average weekly net assets as of October 31, 2023 by dividing the total dollar amount of the management fee by the Fund's average weekly net assets (managed assets less outstanding leverage). |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
FISCAL YEAR ENDED |  | TOTAL AMOUNT OUTSTANDING |  | ASSET COVERAGE |  | LIQUIDATING PREFERENCE PER PREFERRED SHARE(c)​ |  | AVERAGE MARKET VALUE PER PREFERRED SHARE |  | TYPE OF SENIOR SECURITY |
October 31, 2023 |  | $ | 314,400,000 |  |  | $ | 3,564 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2023 |  | $ | 133,000,000 |  |  |  | 211 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2022 |  | $ | 339,400,000 |  |  |  | 3,630 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2022 |  | $ | 133,000,000 |  |  |  | 232 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2021 |  | $ | 399,400,000 |  |  |  | 4,116 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2021 |  | $ | 133,000,000 |  |  |  | 309 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2020 |  | $ | 288,400,000 |  |  |  | 4,431 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2020 |  | $ | 100,000,000 |  |  |  | 319 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2019 |  | $ | 277,400,000 |  |  |  | 4,080 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2019 |  | $ | 100,000,000 |  |  |  | 283 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2018 |  | $ | 288,000,000 |  |  |  | 3,921 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2018 |  | $ | 100,000,000 |  |  |  | 282 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2017 |  | $ | 275,000,000 |  |  |  | 4,265 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2017 |  | $ | 100,000,000 |  |  |  | 293 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2016 |  | $ | 306,000,000 |  |  |  | 3,454 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2015 |  | $ | 353,000,000 |  |  |  | 3,316 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2014 |  | $ | 360,000,000 |  |  |  | 3,588 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
(a)​ Calculated by subtracting the Fund's total liabilities (not including notes payable) from the Fund's total assets and dividing this by the amount of notes payable outstanding, and by multiplying the result by 1,000. (b) ​Calculated by subtracting the Fund's total liabilities (not including MRPS) from the Fund's total assets and dividing this by the number of MRPS outstanding, and by multiplying the result by 25. (c)​ "Liquidating Preference per Preferred Share" means the amount to which a holder of preferred shares would be entitled upon the liquidation of the Fund in preference to common shareholders, expressed as a dollar amount per preferred share. (d)​ The MRPS are not listed on any exchange or automated quotation system. The MRPS are considered debt of the issuer; and the liquidation preference approximates fair value. |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities, Note [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Senior Securities The following table sets forth information regarding the Fund's outstanding bank loans, and mandatory redeemable preferred shares ("MRPS") as of the end of each of the Fund's last ten fiscal years, as applicable. The information in the table shown below comes from the Fund's financial statements for the fiscal year ended October 31, 2023, and each of the prior nine years then ended, all of which have been audited by Deloitte & Touche LLP, the Fund's independent registered public accounting firm.
FISCAL YEAR ENDED |  | TOTAL AMOUNT OUTSTANDING |  | ASSET COVERAGE |  | LIQUIDATING PREFERENCE PER PREFERRED SHARE(c)​ |  | AVERAGE MARKET VALUE PER PREFERRED SHARE |  | TYPE OF SENIOR SECURITY |
October 31, 2023 |  | $ | 314,400,000 |  |  | $ | 3,564 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2023 |  | $ | 133,000,000 |  |  |  | 211 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2022 |  | $ | 339,400,000 |  |  |  | 3,630 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2022 |  | $ | 133,000,000 |  |  |  | 232 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2021 |  | $ | 399,400,000 |  |  |  | 4,116 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2021 |  | $ | 133,000,000 |  |  |  | 309 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2020 |  | $ | 288,400,000 |  |  |  | 4,431 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2020 |  | $ | 100,000,000 |  |  |  | 319 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2019 |  | $ | 277,400,000 |  |  |  | 4,080 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2019 |  | $ | 100,000,000 |  |  |  | 283 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2018 |  | $ | 288,000,000 |  |  |  | 3,921 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2018 |  | $ | 100,000,000 |  |  |  | 282 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2017 |  | $ | 275,000,000 |  |  |  | 4,265 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2017 |  | $ | 100,000,000 |  |  |  | 293 | (b)​ |  |  | 25 |  |  |  | 25 | (d)​ |  | MRPS |
October 31, 2016 |  | $ | 306,000,000 |  |  |  | 3,454 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2015 |  | $ | 353,000,000 |  |  |  | 3,316 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
October 31, 2014 |  | $ | 360,000,000 |  |  |  | 3,588 | (a)​ |  |  | — |  |  |  | — |  |  | Loan |
(a)​ Calculated by subtracting the Fund's total liabilities (not including notes payable) from the Fund's total assets and dividing this by the amount of notes payable outstanding, and by multiplying the result by 1,000. (b) ​Calculated by subtracting the Fund's total liabilities (not including MRPS) from the Fund's total assets and dividing this by the number of MRPS outstanding, and by multiplying the result by 25. (c)​ "Liquidating Preference per Preferred Share" means the amount to which a holder of preferred shares would be entitled upon the liquidation of the Fund in preference to common shareholders, expressed as a dollar amount per preferred share. (d)​ The MRPS are not listed on any exchange or automated quotation system. The MRPS are considered debt of the issuer; and the liquidation preference approximates fair value. |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Averaging Method, Note [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The MRPS are not listed on any exchange or automated quotation system. The MRPS are considered debt of the issuer; and the liquidation preference approximates fair value. |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Highlights Audited, Note [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The following table sets forth information regarding the Fund's outstanding bank loans, and mandatory redeemable preferred shares ("MRPS") as of the end of each of the Fund's last ten fiscal years, as applicable. The information in the table shown below comes from the Fund's financial statements for the fiscal year ended October 31, 2023, and each of the prior nine years then ended, all of which have been audited by Deloitte & Touche LLP, the Fund's independent registered public accounting firm. |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment Objectives and Practices [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | INVESTMENT OBJECTIVE AND STRATEGIES Investment Objective The Fund's investment objective is to provide total return through a combination of capital appreciation and current income. Principal Investment Strategies Under normal circumstances, the Fund invests at least 80% of its managed assets in a diversified portfolio of convertible securities and non-convertible income securities.* The portion of the Fund's assets invested in convertible securities and non-convertible income securities will vary from time to time consistent with the Fund's investment objective, changes in equity prices and changes in interest rates and other economic and market factors, although, under normal circumstances, the Fund will invest at least 35% of its managed assets in convertible securities. The Fund invests in securities with a broad range of maturities. The average term to maturity of the Fund's securities typically will range from two to ten years. "Managed assets" means the Fund's total assets (including any assets attributable to any leverage that may be outstanding) minus total liabilities (other than debt representing financial leverage). The Fund is not limited in the percentage of its assets invested in convertible securities, and investment in convertible securities forms an important part of the Fund's principal investment strategies. A convertible security is a debt security, debenture, note or preferred stock that is exchangeable for an equity security (typically common stock of the same issuer) at a predetermined price (the "conversion price"). Depending upon the relationship of the conversion price to the market value of the underlying security, a convertible security may trade more like an equity security than a debt instrument. The Fund may invest in convertible securities of any rating. The Fund may invest in "synthetic" convertible instruments. A synthetic convertible instrument is a financial instrument (or two or more securities held in tandem) that is designed to simulate the economic characteristics of another instrument (i.e., a convertible security) through the combined economic features of a collection of other securities or assets. Calamos may create a synthetic convertible instrument by combining separate securities that possess the two principal characteristics of a true convertible security, i.e., a fixed-income security ("fixed-income component", which may be a convertible or non-convertible security) and the right to acquire an equity security ("convertible component"). The fixed-income component is achieved by investing in fixed-income securities such as bonds, preferred stocks and money market instruments. The convertible component is achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index. The fixed income and convertible components may have different issuers, and either component may change at any time. The Fund may also invest in synthetic convertible instruments created by third parties, typically investment banks. Synthetic convertible instruments created by such parties may be designed to simulate the characteristics of traditional convertible securities or may be designed to alter or emphasize a particular feature. Synthetic convertible instruments may include structured notes, equity-linked notes, mandatory convertibles and combinations of securities and instruments, such as a debt instrument combined with a forward contract. The Fund's holdings of synthetic convertible instruments are considered convertible securities for purposes of the Fund's policy to invest at least 35% of its managed assets in convertible securities and 80% of its managed assets in a diversified portfolio of convertible securities and non-convertible income securities. The Fund will also invest in non-convertible income securities. The Fund's investments in non-convertible income securities may have fixed or variable principal payments and all types of interest rate and dividend payment and reset terms, including fixed rate, adjustable rate, zero coupon, contingent, deferred, payment in kind and auction rate features. A substantial portion of the Fund's assets may be invested in below investment grade (high yield, high risk) securities for either current income or capital appreciation or both. These securities are rated Ba or lower by Moody's Investors Service, Inc. or BB or lower by Standard & Poor's Financial Services, LLC, a subsidiary of The McGraw-Hill Companies, Inc. or are unrated securities of comparable quality as determined by Calamos, the Fund's investment adviser. The Fund may invest in high yield securities of any rating. The Fund may, but currently does not intend to, invest up to 5% of its managed assets in distressed securities that are in default or the issuers of which are in bankruptcy. * This is a non-fundamental policy and may be changed by the Board of Trustees of the Fund provided that shareholders are provided with at least 60 days' prior written notice of any change as required by the rules under the 1940 Act. Although the Fund primarily invests in securities of US issuers, the Fund may invest up to 25% of its net assets in securities of foreign issuers in developed and emerging markets, including debt and equity securities of corporate issuers and debt securities of government issuers. The Fund may seek to generate income from option premiums by writing (selling) options. The Fund may write (sell) call options (i) on a portion of the equity securities (including equity securities obtainable by the Fund through the exercise of its rights with respect to convertible securities it owns) in the Fund's portfolio and (ii) on broad-based securities indices (such as the Standard and Poor's 500®​ Index ("S&P 500") or the MSCI EAFE®​ Index ("MSCI EAFE"), which is an index of international equity stocks) or certain ETFs (exchange traded funds) that trade like common stocks but seek to replicate such market indices. In addition, to seek to offset some of the risk of a potential decline in value of certain long positions, the Fund may also purchase put options on individual securities, broad-based securities indices (such as the S&P 500 or the MSCI EAFE), or certain ETFs that trade like common stocks but seek to replicate such market indices. The Fund may invest without limit in certain securities ("Rule 144A Securities"), such as convertible and debt securities, that are typically purchased in transactions exempt from the registration requirements of the 1933 Act pursuant to Rule 144A under that Act. Under the supervision and oversight of the Fund's Board of Trustees, Calamos will determine whether Rule 144A Securities are liquid. Typically, the Fund purchases Rule 144A Securities only if Calamos has determined them to be liquid. The Fund may invest in loan participations and other direct claims against a borrower. The corporate loans in which the Fund may invest primarily consist of direct obligations of a borrower and may include debtor in possession financings pursuant to Chapter 11 of the US Bankruptcy Code, obligations of a borrower issued in connection with a restructuring pursuant to Chapter 11 of the US Bankruptcy Code, leveraged buy-out loans, leveraged recapitalization loans, receivables purchase facilities, and privately placed notes. The Fund may invest in a corporate loan at origination as a co-lender or by acquiring in the secondary market participations in, assignments of or novations of a corporate loan. Many such loans are secured, although some may be unsecured. Such loans may be in default at the time of purchase. In addition, loan participations involve a risk of insolvency of the lending bank or other financial intermediary. The markets in such loans are not regulated by federal securities laws or the Commission. The Fund may invest in other securities of various types to the extent consistent with its investment objective. Normally, the Fund invests substantially all of its assets to meet its investment objective. For temporary defensive purposes, the Fund may depart from its principal investment strategies and invest part or all of its assets in securities with remaining maturities of less than one year or cash equivalents; or it may hold cash. During such periods, the Fund may not be able to achieve its investment objective. There are no restrictions as to the ratings of debt securities acquired by the Fund or the portion of the Fund's assets that may be invested in debt securities in a particular ratings category. The Fund currently uses, and may in the future use, financial leverage. The Fund has obtained financial leverage (i) under an Amended and Restated Liquidity Agreement with State Street Bank and Trust Company that allows the Fund to borrow up to $430 million and (ii) through the issuance of four series of Mandatory Redeemable Preferred Shares ("MRPS" or "MRP Shares") with an aggregate liquidation preference of $133.0 million. |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Principal Risks of the Funds The factors that are most likely to have a material effect on a particular Fund's portfolio as a whole are called "principal risks." Each Fund is subject to the principal risks indicated below, whether through direct investment or derivative positions. Each Fund may be subject to additional risks other than those identified and described below because the types of investments made by a Fund can change over time.
Portfolio Level Risks |  | CPZ |  | CGO |  | CCD |  | CSQ |  | CHW |  | CHI |  | CHY |
American Depositary Receipts Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Antitakeover Provisions |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Cash Holdings Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Contingent Liabilities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Convertible Hedging/Short Sales Risk |  |  |  |  |  |  |  |  |  |  | x |  |  |  |  |  |
Convertible Securities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Correlation Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Counterparty and Settlement Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Covenant-Lite Loans Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Credit Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Debt Securities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Decline in Net Asset Value Risk |  |  | x |  |  |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Default Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Derivatives Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Diminished Voting Power and Excess Cash Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Duration Mismatch Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Duration Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Early Redemption Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Emerging Markets Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Equity Securities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Fixed Income Securities Risk |  |  |  |  |  |  | x |  |  |  |  |  |  |  |  |  |
Foreign Securities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Forward Currency Exchange Contract Risks |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Futures and Forward Contracts Risk |  |  | x |  |  |  | x |  |  |  |  |  | x |  |  |  | x |  |  |  |  |  |
General Derivative Risks |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Geographic Concentration Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  | x |  |  |  | x |  |
Geographic Focus Risk |  |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  |  |  |
High Yield Securities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Interest Rate Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Interest Rate Transactions Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Leverage Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Liquidity Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Management Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Market Discount Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Master Limited Partnership Risk |  |  |  |  |  |  | x |  |  |  | x |  |  |  |  |  | x |  |  |  | x |  |
Maturity Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Non-Convertible Income Securities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Non-US Government Obligation Risk |  |  | x |  |  |  | x |  |  |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Other Investment Companies (including ETFs) Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  |  |  | x |  |
Portfolio Selection Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Portfolio Turnover Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Preferred Share Liquidation Preference Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recent Market Events |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
REIT Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  |  |  | x |  |  |  | x |  |
Portfolio Level Risks |  | CPZ |  | CGO |  | CCD |  | CSQ |  | CHW |  | CHI |  | CHY |
Risks Associated with Options |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Rule 144A Securities Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Sector Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Short Selling Risk |  |  | x |  |  |  |  |  | x |  |  |  |  |  | x |  |  |  |  |  |
Synthetic Convertible Instruments Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Tax Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
US Government Security Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Volatility Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fund Level and Other Risks |  | CPZ |  | CGO |  | CCD |  | CSQ |  | CHW |  | CHI |  | CHY |
Currency Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Cybersecurity Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Inflation Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Leverage Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Limited Term Risk |  |  | x |  |  |  |  |  | x |  |  |  |  |  |  |  |  |  |
Loan Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Market Discount Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Market Disruption Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Market Impact Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Ratings and Asset Coverage Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Reduction of Leverage Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Regulatory Risk |  |  | x |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secondary Market Risk |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Senior Leverage Risk |  |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |  |  | x |  |
Portfolio Level Risks American Depositary Receipts Risk. The stocks of most foreign companies that trade in the US markets are traded as ADRs. US depositary banks issue these stocks. Each ADR represents one or more shares of foreign stock or a fraction of a share. The price of an ADR corresponds to the price of the foreign stock in its home market, adjusted to the ratio of the ADRs to foreign company shares. Therefore, while purchasing a security on a US exchange, the risks inherently associated with foreign investing still apply to ADRs. Antitakeover Provisions. The Fund's Agreement and Declaration of Trust and By-Laws include provisions that could limit the ability of other entities or persons to acquire control of the Fund or to change the composition of its Board of Trustees. Such provisions could limit the ability of shareholders to sell their shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. These provisions include staggered terms of office for the Trustees, advance notice requirements for shareholder proposals, and super-majority voting requirements for certain transactions with affiliates, converting the Fund to an open-end investment company or a merger, asset sale or similar transaction. Holders of preferred shares have voting rights in addition to and separate from the voting rights of common shareholders with respect to certain of these matters. Holders of any preferred shares, voting separately as a single class, have the right to elect at least two Trustees at all times. The holders of preferred shares or debt, if any, on the one hand, and the holders of the common shares, on the other, may have interests that conflict with each other in certain situations, including conflicts that relate to the fees and expenses of the Fund. Cash Holdings Risk. To the extent the Fund holds cash positions, the Fund risks achieving lower returns and potential lost opportunities to participate in market appreciation which could negatively impact the Fund's performance and ability to achieve its investment objective. Contingent Liabilities Risk. Entering into derivative contracts in order to pursue the Fund's various hedging strategies could require the Fund to fund cash payments in the future under certain circumstances, including an event of default or other early termination event, or the decision by a counterparty to request margin in the form of securities or other forms of collateral under the terms of the derivative contract or applicable laws. The amounts due with respect to a derivative contract would generally be equal to the unrealized loss of the open positions with the respective counterparty and could also include other fees and charges. These payments are contingent liabilities and therefore may not appear on the Fund's balance sheet. The Fund's ability to fund these contingent liabilities will depend on the liquidity of the Fund's assets and access to capital at the time, and the need to fund these contingent liabilities could adversely impact the Fund's financial condition. Convertible Hedging/Short Sales Risk. The Fund may incur a loss (without limit) as a result of a short sale if the market value of the borrowed security increases between the date of the short sale and the date the Fund replaces the security. The Fund may be unable to repurchase the borrowed security at a particular time or at an acceptable price. If the market price of the common stock issuable upon exercise of a convertible security increases above the conversion price on the convertible security, the price of the convertible security will increase. The Fund's increased liability on the short position would, in whole or in part, reduce this gain. If the price of the common stock declines, any decline in the price of the convertible security would offset, in whole or in part, the Fund's gain on the short position. The use of short sales could increase the Fund's exposure to the market, magnify losses and increase the volatility of returns. Convertible Securities Risk. The value of a convertible security is influenced by both the yield of non- convertible securities of comparable issuers and by the value of the underlying common stock. The value of a convertible security viewed without regard to its conversion feature (i.e., strictly on the basis of its yield) is sometimes referred to as its "investment value." A convertible security's investment value tends to decline as prevailing interest rate levels increase. Conversely, a convertible security's investment value tends to increase as prevailing interest rate levels decline. Correlation Risk. Imperfect correlation between the value of derivative instruments and the underlying assets of the Fund creates the possibility that the loss on such instruments may be greater than the gain in the value of the underlying assets in the Fund's portfolio. Counterparty and Settlement Risk (all Funds except CPZ). Trading options, futures contracts, swaps and other derivative financial instruments entails credit risk with respect to the counterparties with whom and through which the Fund trades. Such instruments when traded over the counter do not include the same protections as may apply to trading derivatives on organized Calamos—We note that CPZ includes a more robust version of this risk disclosure. We think it is appropriate to include this version as well. exchanges. Substantial losses may arise from the insolvency, bankruptcy or default of a counterparty and risk of settlement default of parties with whom the Fund trades securities. This risk may be heightened during volatile market conditions. Settlement mechanisms in emerging markets are generally less developed and reliable than those in more developed countries, thus increasing the risks. In the past, broker-dealers and other financial institutions have experienced extreme financial difficulty, sometimes resulting in bankruptcy of the institution. Although Calamos monitors the creditworthiness of the Fund's counterparties, there can be no assurance that the Fund's counterparties will not experience similar difficulties, possibly resulting in losses to the Fund. If a counterparty becomes bankrupt, or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances. Material exposure to a single or small group of counterparties increases the Fund's counterparty risk. Counterparty and Settlement Risk (CPZ). Trading options, futures contracts, swaps and other derivative financial instruments entails credit risk with respect to the counterparties with whom and through which the Fund trades. Such instruments when traded over the counter do not include the same protections as may apply to trading derivatives on organized exchanges. Substantial losses may arise from the insolvency, bankruptcy or default of a counterparty and risk of settlement default of parties with whom the Fund trades securities. This risk may be heightened during volatile market conditions. Settlement mechanisms in emerging markets are generally less developed and reliable than those in more developed countries, thus increasing the risks. Counterparty risk is the risk that the other party in a derivative transaction will not fulfill its contractual obligation. Changes in the credit quality of the Fund's counterparties with respect to its derivative transactions may affect the value of those instruments. By entering into derivatives, the Fund assumes the risk that its counterparties could experience financial hardships that could call into question their continued ability to perform their obligations. As a result, concentrations of such derivatives in any one counterparty would subject the Fund to an additional degree of risk with respect to defaults by such counterparty. "Covenant-Lite" Loans Risk. Some of the loans in which the Fund may invest may be "covenant-lite" loans, which means the loans contain fewer or no maintenance covenants than other loans and do not include terms which allow the lender to monitor the performance of the borrower and declare a default if certain criteria are breached. The Fund may experience delays in enforcing its rights on its holdings of covenant-lite loans. However, a convertible security's market value tends to reflect the market price of the common stock of the issuing company when that stock price is greater than the convertible security's "conversion price." The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security and changes in interest rates. Thus, the convertible security may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities would be paid before the company's common stockholders. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, such bankruptcy or failure to perform is likely to result in a default under such derivative contract, unless such default is cured. Default by a party with whom the Fund enters into a hedging transaction may result in the loss of unrealized profits, leaving the Fund with unsecured exposure and force the Fund to cover its resale commitments, if any, at the then current market price. It may not always be possible to dispose of or close out a hedging position without the consent of the hedging counterparty, and the Fund may not be able to enter into an offsetting contract in order to cover its risk. The Fund cannot assure its shareholders that a liquid secondary market will exist for hedging instruments purchased or sold, and the Fund may be required to maintain a position until exercise or expiration, which could result in losses. Furthermore, upon the bankruptcy of a counterparty, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a dissolution, assignment for the benefit of creditors, liquidation, winding-up, bankruptcy, or other analogous proceeding. In addition, in the event of the insolvency of a counterparty to a derivative transaction, the derivative transaction would typically be terminated at its fair market value. If the Fund is owed this fair market value in the termination of the derivative transaction and its claim is unsecured, the Fund will be treated as a general creditor of such counterparty, and will not have any claim with respect to the underlying security. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances and the enforceability of agreements for hedging transactions may depend on compliance with applicable statutory and other regulatory requirements and, depending on the identity of the counterparty, applicable international requirements. Certain interest rate and credit default swaps are subject to mandatory clearing, in which case a central clearing counterparty stands between each buyer and seller and effectively guarantees performance of each derivative contract, to the extent of its available resources for such purpose. As a result, the counterparty risk is now shifted from bilateral risk between the parties to the individual credit risk of the central clearing counterparty and the futures commission merchant through which the Fund holds its cleared position. Even in such case, there can be no assurance that a clearing house, or its members, will satisfy the clearing house's obligations to the Fund. Uncleared derivatives have no such protection; each party bears the risk that its direct counterparty will default. Credit Risk. An issuer of a fixed income security could be downgraded or default. If the Fund holds securities that have been downgraded, or that default on payment, the Fund's performance could be negatively affected. Debt Securities Risk. The Fund may invest in debt securities, including corporate bonds and high yield securities. In addition to the risks described elsewhere in the Fund's prospectus (such as high yield securities risk and interest rate risk), debt securities are subject to certain additional risks, including issuer risk and reinvestment risk. Issuer risk is the risk that the value of debt securities may decline for a number of reasons which directly relate to the issuer, such as management performance, leverage and reduced demand for the issuer's goods and services. Reinvestment risk is the risk that income from the Fund's portfolio will decline if the Fund invests the proceeds from matured, traded or called bonds at market interest rates that are below the Fund portfolio's current earnings rate. A decline in income could affect the market price of the Fund's common shares or the overall return of the Fund. Decline in Net Asset Value Risk. A material decline in the Fund's NAV may impair the Fund's ability to maintain required levels of asset coverage for any outstanding borrowings or any debt securities or preferred shares. Default Risk. Default risk refers to the risk that a company that issues a convertible or debt security will be unable to fulfill its obligations to repay principal and interest. The lower a debt security is rated, the greater its default risk. As a result, the Fund may incur cost and delays in enforcing its rights against the defaulting issuer. Derivatives Risk. Generally, derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index, and may relate to individual debt or equity instruments, interest rates, currencies or currency exchange rates, commodities, related indexes and other assets. The Fund may utilize a variety of derivative instruments including, but not limited to, interest rate swaps, caps, and floors, convertible securities, synthetic convertible instruments, options on individual securities, index options, long calls, covered calls, long puts, cash-secured short puts and protective puts for hedging, risk management and investment purposes. The Fund's use of derivative instruments involves investment risks and transaction costs to which the Fund would not be subject absent the use of these instruments and, accordingly, may result in losses greater than if they had not been used. The use of derivative instruments may have risks including, among others, leverage risk, duration mismatch risk, correlation risk, liquidity risk, interest rate risk, volatility risk, credit risk, management risk and counterparty risk. Derivatives also involve the risk of mispricing or improper valuation and the risk that changes in the value of a derivative may not correlate perfectly with an underlying asset, interest rate or index. Suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Fund will engage in these transactions to reduce exposure to other risks when that would be beneficial. Furthermore, the skills needed to employ derivatives strategies are different from those needed to select portfolio securities and, in connection with such strategies, the Fund makes predictions with respect to market conditions, liquidity, currency movements, market values, interest rates and other applicable factors, which may be inaccurate. Thus, the use of derivative instruments may require the Fund to sell or purchase portfolio securities at inopportune times or for prices below or above the current market values, may limit the amount of appreciation the Fund can realize on an investment or may cause the Fund to hold a security that it might otherwise want to sell. Tax rules governing the Fund's transactions in derivative instruments may also affect whether gains and losses recognized by the Fund are treated as ordinary or capital, accelerate the recognition of income or gains to the Fund, defer losses to the Fund, and cause adjustments in the holding periods of the Fund's securities, thereby affecting, among other things, whether capital gains and losses are treated as short-term or long-term. These rules could therefore affect the amount, timing and/or character of distributions to shareholders. In addition, there may be situations in which the Fund elects not to use derivative instruments that result in losses greater than if they had been used. Amounts paid by the Fund as premiums and cash or other assets held in margin accounts with respect to the Fund's derivative instruments would not be available to the Fund for other investment purposes, which may result in lost opportunities for gain. Derivative instruments can be illiquid, may disproportionately increase losses and may have a potentially large impact on Fund performance. Diminished Voting Power and Excess Cash Risk. The voting power of current shareholders will be diluted to the extent that such shareholders do not purchase shares in any future common share offerings or do not purchase sufficient shares to maintain their percentage interest. In addition, if the Fund is unable to invest the proceeds of such offering as intended, its per share distribution may decrease (or may consist of return of capital) and the Fund may not participate in market advances to the same extent as if such proceeds were fully invested as planned. Duration Mismatch Risk. The duration of a derivative instrument may be significantly different than the duration of the related liability or asset. Duration Risk. Duration measures the time-weighted expected cash flows of a fixed-income security, which can determine its sensitivity to changes in the general level of interest rates. The value of securities with longer durations tend to be more sensitive to interest rate changes than securities with shorter durations. The longer the Fund's dollar-weighted average duration, the more its value can generally be expected to be sensitive to interest rate changes than a fund with a shorter dollar-weighted average duration. Duration differs from maturity in that it considers a security's coupon payments in addition to the amount of time until the security matures. Various techniques may be used to shorten or lengthen the Fund's duration. As the value of a security changes over time, so will its duration. Early Redemption Risk. The Fund may voluntarily redeem preferred shares or may be forced to redeem preferred shares to meet regulatory requirements and the asset coverage requirements of the preferred shares. Such redemptions may be at a time that is unfavorable to holders of the preferred shares Emerging Markets Risk. Emerging market countries may have relatively unstable governments and economies based on only a few industries, which may cause greater instability. The value of emerging market securities will likely be particularly sensitive to changes in the economies of such countries. These countries are also more likely to experience higher levels of inflation, deflation or currency devaluations, which could adversely affect the value of the Fund's investments and hurt those countries' economies and securities markets. Securities issued in these countries may be more volatile and less liquid than securities issued in foreign countries with more developed economies or markets. Loss may also result from the imposition of exchange controls, confiscations and other government restrictions, or from problems in share registration, settlement, custody, or other operational risks. Equity Securities Risk. Equity investments are subject to greater fluctuations in market value than other asset classes as a result of such factors as the issuer's business performance, investor perceptions, stock market trends and general economic conditions. Equity securities are subordinated to bonds and other debt instruments in a company's capital structure in terms of priority to corporate income and liquidation payments. The Fund may invest in preferred stocks and convertible securities of any rating, including below investment grade. Below investment grade securities or comparable unrated securities are considered predominantly speculative with respect to the issuer's ability to pay interest and principal and are susceptible to default or decline in market value due to adverse economic and business developments. The market values for below investment grade securities tend to be very volatile, and these securities are generally less liquid than investment- grade debt securities. For these reasons, your investment in the Fund is subject to the following specific risks: • increased price sensitivity to changing interest rates and to a deteriorating economic environment; • greater risk of loss due to default or declining credit quality; • adverse company specific events are more likely to render the issuer unable to make interest and/or principal payments; and • if a negative perception of the below investment grade market develops, the price and liquidity of below investment grade securities may be depressed. This negative perception could last for a significant period of time. Fixed Income Securities Risk. The Fund may invest in fixed income securities, including corporate, municipal, and government bonds. Fixed income securities are subject to the risk of decreasing value in periods of increasing interest rates, as well as the risk that the issuer of such securities could be downgraded or default, causing the credit rating of the securities to drop and thus generally decreasing the value of such securities. Foreign Securities Risk. Investments in non-US issuers may involve unique risks compared to investing in securities of US issuers. These risks are more pronounced to the extent that the Fund invests a significant portion of its non-US investments in one region or in the securities of emerging market issuers. These risks may include: • less information may be available about non-US issuers or markets due to less rigorous disclosure or accounting standards or regulatory practices in foreign jurisdictions; • many non-US markets are smaller, less liquid and more volatile. In a changing market, Calamos may not be able to sell the Fund's portfolio securities at times, in amounts and at prices it considers reasonable; • an adverse effect of currency exchange rate changes or controls on the value of the Fund's investments; • the economies of non-US countries may grow at slower rates than expected or may experience a downturn or recession; • economic, political and social developments may adversely affect the securities markets in foreign jurisdictions, including expropriation and nationalization; • the difficulty in obtaining or enforcing a court judgment in non-US countries; • restrictions on foreign investments in non-US jurisdictions; • difficulties in effecting the repatriation of capital invested in non-US countries; • withholding and other non-US taxes may decrease the Fund's return; • the ability for the Public Company Accounting Oversight Board, which regulates auditors of US public companies, is unable to inspect audit work papers in certain foreign countries; • often limited rights and few practical remedies to pursue shareholder claims, including class actions or fraud claims, and the ability of the Commission, the US Department of Justice and other authorities to bring and enforce actions against foreign issuers or foreign persons is limited; and • dividend income the Fund receives from foreign securities may not be eligible for the special tax treatment applicable to qualified dividend income. Based upon the Fund's test for determining whether an issuer is a "foreign issuer", it is possible that an issuer of securities in which the Fund invests could be organized under the laws of a foreign country, yet still conduct a substantial portion of its business in the US or have substantial assets in the US. In this case, such a "foreign issuer" may be subject to the market conditions in the US to a greater extent than it may be subject to the market conditions in the country of its organization. There may be less publicly available information about non-US markets and issuers than is available with respect to US securities and issuers. Non-US companies generally are not subject to accounting, auditing and financial reporting standards, practices and requirements comparable to those applicable to US companies. The trading markets for most non-US securities are generally less liquid and subject to greater price volatility than the markets for comparable securities in the United States. The markets for securities in certain emerging markets are in the earliest stages of their development. Even the markets for relatively widely traded securities in certain non-US markets, including emerging market countries, may not be able to absorb, without price disruptions, a significant increase in trading volume or trades of a size customarily undertaken by institutional investors in the United States. Additionally, market making and arbitrage activities are generally less extensive in such markets, which may contribute to increased volatility and reduced liquidity. Economies and social and political conditions in individual countries may differ unfavorably from those in the United States. Non-US economies may have less favorable rates of growth of gross domestic product, rates of inflation, currency valuation, capital reinvestment, resource self-sufficiency and balance of payments positions. Many countries have experienced substantial, and in some cases extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, very negative effects on the economies and securities markets of certain emerging countries. Unanticipated political or social developments may also affect the values of the Fund's investments and the availability to the Fund of additional investments in such countries. Forward Currency Exchange Contracts Risk. Forward contracts are contractual agreements to purchase or sell a specified currency at a specified future date (or within a specified time period) at a price set at the time of the contract. The Fund may not fully benefit from, or may lose money on, forward currency exchange transactions if changes in currency exchange rates do not occur as anticipated or do not correspond accurately to changes in the value of the Fund's holdings. Futures and Forward Contracts Risk. Futures contracts provide for the future sale by one party and purchase by another of a specific asset at a specific time and price (with or without delivery required). Futures contracts are standardized contracts traded on a recognized exchange. An option on a futures contract gives the purchaser the right, in exchange for a premium, to assume a position in a futures contract at a specified exercise price during the term of the option. Futures and forward contracts are subject to counterparty risk, meaning that the party who issues the derivatives (the clearinghouse or the broker holding the Fund's position for a futures contract or the counterparty for a forward contract) may experience a significant credit event and may be unwilling or unable to make timely settlement payments or otherwise honor its obligations. General Derivative Risks. Derivatives also involve the risk of mispricing or improper valuation and the risk that changes in the value of a derivative may not correlate perfectly with an underlying asset, interest rate or index. Suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Fund will engage in these transactions to reduce exposure to other risks when that would be beneficial. Furthermore, the skills needed to employ derivatives strategies are different from those needed to select portfolio securities and, in connection with such strategies, the Fund may make predictions with respect to market conditions, liquidity, currency movements, market values, interest rates and other applicable factors, which may be inaccurate. Thus, the use of derivative instruments may require the Fund to sell or purchase portfolio securities at inopportune times or for prices below or above the current market values, may limit the amount of appreciation the Fund can realize on an investment or may cause the Fund to hold a security that it might otherwise want to sell. Tax rules governing the Fund's transactions in derivative instruments may also affect whether gains and losses recognized by the Fund are treated as ordinary or capital, accelerate the recognition of income or gains to the Fund, defer losses to the Fund, and cause adjustments in the holding periods of the Fund's securities, thereby affecting, among other things, whether capital gains and losses are treated as short-term or long-term. These rules could therefore affect the amount, timing and/or character of distributions to shareholders. In addition, there may be situations in which the Fund elects not to use derivative instruments that result in losses greater than if they had been used. Amounts paid by the Fund as premiums and cash or other assets held in margin accounts with respect to the Fund's derivative instruments would not be available to the Fund for other investment purposes, which may result in lost opportunities for gain. Derivative instruments can be illiquid, may disproportionately increase losses and may have a potentially large impact on Fund performance. Geographic Concentration Risk. Investments in a particular country or geographic region may be particularly susceptible to political, diplomatic or economic conditions and regulatory requirements. To the extent the Fund concentrates its investments in a particular country, region or group of regions, the Fund may be more volatile than a more geographically diversified fund. Geographic Focus Risk. Investments in a particular country or geographic region may be particularly susceptible to political, diplomatic or economic conditions and regulatory requirements. To the extent the Fund focuses its investments in a particular country, region or group of regions, the Fund may be more volatile than a more geographically diversified fund. High Yield Securities Risk. The Fund may invest in high yield securities of any rating. Investment in high yield securities involves substantial risk of loss. Below investment grade non-convertible debt securities or comparable unrated securities are commonly referred to as "junk bonds" and are considered predominantly speculative with respect to the issuer's ability to pay interest and principal and are susceptible to default or decline in market value due to adverse economic and business developments. The market values for high yield securities tend to be very volatile, and these securities are less liquid than investment grade debt securities. For these reasons, your investment in the Fund is subject to the following specific risks: • increased price sensitivity to changing interest rates and to a deteriorating economic environment; • greater risk of loss due to default or declining credit quality; • adverse company specific events are more likely to render the issuer unable to make interest and/or principal payments; and • if a negative perception of the high yield market develops, the price and liquidity of high yield securities may be depressed. This negative perception could last for a significant period of time. Adverse changes in economic conditions are more likely to lead to a weakened capacity of a high yield issuer to make principal payments and interest payments than an investment grade issuer. The principal amount of high yield securities outstanding has proliferated in the past decade as an increasing number of issuers have used high yield securities for corporate financing. An economic downturn could severely affect the ability of highly leveraged issuers to service their debt obligations or to repay their obligations upon maturity. The Fund may incur additional expenses to the extent it is required to seek recovery upon a default in payment of principal or interest on its portfolio holdings. In certain circumstances, the Fund may be required to foreclose on an issuer's assets and take possession of its property or operations. In such circumstances, the Fund would incur additional costs in disposing of such assets and potential liabilities from operating any business acquired. The secondary market for high yield securities may not be as liquid as the secondary market for more highly rated securities, a factor which may have an adverse effect on the Fund's ability to dispose of a particular security. There are fewer dealers in the market for high yield securities than for investment grade obligations. The prices quoted by different dealers may vary significantly and the spread between the bid and asked price is generally much larger than for higher quality instruments. Under adverse market or economic conditions, the secondary market for high yield securities could contract further, independent of any specific adverse changes in the condition of a particular issuer, and these instruments may become illiquid. As a result, the Fund could find it more difficult to sell these securities or may be able to sell the securities only at prices lower than if such securities were widely traded. Prices realized upon the sale of such lower rated or unrated securities, under these circumstances, may be less than the prices used in calculating the Fund's NAV. Interest Rate Risk. In addition to the risks described above, debt securities, including high yield securities, are subject to certain risks, including: • if interest rates go up, the value of debt securities in the Fund's portfolio generally will decline; • during periods of declining interest rates, the issuer of a security may exercise its option to prepay principal earlier than scheduled, forcing the Fund to reinvest in lower yielding securities. This is known as call or prepayment risk. Debt securities frequently have call features that allow the issuer to repurchase the security prior to its stated maturity. An issuer may redeem an obligation if the issuer can refinance the debt at a lower cost due to declining interest rates or an improvement in the credit standing of the issuer; • during periods of rising interest rates, the average life of certain types of securities may be extended because of slower than expected principal payments. This may lock in a below market interest rate, increase the estimated period until the security is paid in full and reduce the value of the security. This is known as extension risk; • rising interest rates could result in an increase in the cost of the Fund's leverage and could adversely affect the ability of the Fund to meet asset coverage requirements with respect to leverage; • variable rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. When the Fund holds variable rate securities, a decrease in market interest rates will adversely affect the income received from such securities and the NAV of the Fund's shares; and • to the extent the Federal Reserve Board continues to raise interest rates, there is a risk that interest rates across the financial system may also rise. Increases in volatility and interest rates in the fixed-income market may expose the Fund to heightened interest rate risk. Interest Rate Transactions Risk. The Fund may enter into an interest rate swap, cap or floor transaction to attempt to protect itself from increasing dividend or interest expenses on its leverage resulting from increasing short-term interest rates and to hedge its portfolio securities. A decline in interest rates may result in a decline in the value of the swap or cap, which may result in a decline in the NAV of the Fund. Depending on the state of interest rates in general, the Fund's use of interest rate swap or cap transactions could enhance or harm the overall performance of the common shares. To the extent there is a decline in interest rates, the value of the interest rate swap or cap could decline and could result in a decline in the NAV of the common shares. In addition, if the counterparty to an interest rate swap or cap defaults, the Fund would not be able to use the anticipated net receipts under the swap or cap to offset the dividend or interest payments on the Fund's leverage or offset certain losses in its portfolio. Depending on whether the Fund would be entitled to receive net payments from the counterparty on the swap or cap, which in turn would depend on the general state of short-term interest rates at that point in time, such a default could negatively impact the performance of the common shares. In addition, at the time an interest rate swap or cap transaction reaches its scheduled termination date, there is a risk that the Fund would not be able to obtain a replacement transaction or that the terms of the replacement would not be as favorable as on the expiring transaction. If either of these events occurs, it could have a negative impact on the performance of the common shares. If the Fund fails to maintain a required 200% asset coverage of the liquidation value of any outstanding preferred shares or if the Fund loses its rating on its preferred shares or fails to maintain other covenants with respect to the preferred shares, the Fund may be required to redeem some or all of the preferred shares. Similarly, the Fund could be required to prepay the principal amount of any debt securities or other borrowings. Such redemption or prepayment would likely result in the Fund seeking to terminate early all or a portion of any swap or cap transaction. Early termination of a swap could result in a termination payment by or to the Fund. Early termination of a cap could result in a termination payment to the Fund. The Fund intends to segregate with its custodian cash or liquid securities having a value at least equal to the Fund's net payment obligations under any swap transaction, marked-to-market daily. Currently, certain categories of interest rate swaps are subject to mandatory clearing, and more are expected to be cleared in the future. The counterparty risk for cleared derivatives is generally lower than for uncleared OTC derivative transactions because generally a clearing organization becomes substituted for each counterparty to a cleared derivative contract and, in effect, guarantees the parties' performance under the contract as each party to a trade looks only to the clearing house for performance of financial obligations. However, there can be no assurance that a clearing house, or its members, will satisfy the clearing house's obligations to the Fund. Leverage Risk. The derivative instruments in which the Fund may invest will give rise to forms of financial leverage, which may magnify the risk of owning such instruments. Derivatives generally involve leverage in the sense that the investment exposure created by the derivatives may be significantly greater than the Fund's initial investment in the derivative. Accordingly, if the Fund enters into a derivative transaction, it could lose substantially more than the principal amount invested. Additionally, as a closed-end investment company registered with the SEC, the Fund is subject to the federal securities laws, including the 1940 Act, the rules thereunder, and various SEC and SEC staff interpretive positions. In accordance with these laws, rules and positions, the Fund may "set aside" liquid assets (often referred to as "asset segregation"), or engage in other SEC or staff-approved measures, to "cover" open positions with respect to certain portfolio management techniques, such as engaging in reverse repurchase agreements, dollar rolls, entering into credit default swaps or futures contracts, or purchasing securities on a when-issued or delayed delivery basis, that may be considered senior securities under the 1940 Act. The Fund intends to cover its derivative positions by maintaining an amount of cash or liquid securities in a segregated account equal to the face value of those positions and by offsetting derivative positions against one another or against other assets to manage the effective market exposure resulting from derivatives in its portfolio. To the extent that the Fund does not segregate liquid assets or otherwise cover its obligations under such transactions, such transactions will be treated as senior securities representing indebtedness for purposes of the requirement under the 1940 Act that the Fund may not enter into any such transactions if the Fund's borrowings would thereby exceed 33 1/3% of its managed assets, less all liabilities and indebtedness of the Fund not represented by senior securities. However, these transactions, even if covered, may represent a form of economic leverage and will create risks. In addition, these segregation and coverage requirements could result in the Fund maintaining securities positions that it would otherwise liquidate, segregating assets at a time when it might be disadvantageous to do so or otherwise restricting portfolio management. Such segregation and cover requirements will not limit or offset losses on related positions. Liquidity Risk. The Fund may invest without limit in securities that, at the time of investment, are illiquid (i.e., any investment that the Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment). The Fund may also invest without limit in Rule 144A Securities determined to be liquid. Calamos, under the supervision and oversight of the Board of Trustees, will determine whether Rule 144A Securities are illiquid (that is, not readily marketable). Illiquid securities may be difficult to dispose of at a fair price at the times when the Fund believes it is desirable to do so. Investment of the Fund's assets in illiquid securities may restrict the Fund's ability to take advantage of market opportunities. The market price of illiquid securities generally is more volatile than that of more liquid securities, which may adversely affect the price that the Fund pays for or recovers upon the sale of illiquid securities. Illiquid securities are also more difficult to value and may be fair valued in which case Calamos' judgment may play a greater role in the valuation process. The risks associated with illiquid securities may be particularly acute in situations in which the Fund's operations require cash and could result in the Fund borrowing to meet its short-term needs or incurring losses on the sale of illiquid securities. The Fund may also invest without limitation in securities that have not been registered for public sale, but that are eligible for purchase and sale by certain qualified institutional buyers. Management Risk. Calamos' judgment about the attractiveness, relative value or potential appreciation of a particular sector, security or investment strategy may prove to be incorrect. Market Discount Risk. The market price of exchanged-listed preferred shares that the Fund may issue may also be affected by such factors as the Fund's use of leverage, dividend stability, portfolio credit quality, liquidity, and the Fund's dividends paid (which are, in turn, affected by expenses), call protection for portfolio securities and interest rate movements. Master Limited Partnerships Risk. Investments in MLPs involve risks that differ from investments in common stock. Holders of MLP common units are subject to certain risks inherent in the structure of MLPs, including (i) tax risks, (ii) risk related to limited control of management or the general partner or managing member, (iii) limited rights to vote on matters affecting the MLP, except with respect to extraordinary transactions, (iv) conflicts of interest between the general partner or managing member and its affiliates, on the one hand, and the limited partners or members, on the other hand, including those arising from incentive distribution payments or corporate opportunities, and (v) cash flow risks. MLP common units and other equity securities can be affected by macro-economic and other factors affecting the stock market in general, expectations of interest rates, investor sentiment towards MLPs or the energy sector, changes in a particular issuer's financial condition, or unfavorable or unanticipated poor performance of a particular issuer (in the case of MLPs, generally measured in terms of distributable cash flow). Prices of common units of individual MLPs and other equity securities also can be affected by fundamentals unique to the partnership or company, including cash flow growth, cash generating power and distribution coverage. Although certain MLPs may trade on national securities exchanges, certain MLPs may trade less frequently than those of larger companies due to their market capitalizations. Due to limited trading volumes of certain MLPs, the prices of such MLPs may display abrupt or erratic movements at times. Additionally, it may be more difficult for the Fund to buy and sell significant amounts of such securities without an unfavorable impact on prevailing market prices. The Fund's investment in securities that are less actively traded or over time experience decreased trading volume may restrict its ability to dispose of the securities at a fair price. Such a situation may prevent the Fund from limiting losses or realizing gains. This also may adversely affect the Fund's ability to make dividend distributions to shareholders. MLPs are generally treated as partnerships for US federal income tax purposes. Partnerships do not pay US federal income tax at the partnership level. Rather, each partner is allocated a share of the partnership's income, gains, losses, deductions and expenses. A change in current tax law, or a change in the business of a given MLP, could result in an MLP being treated as a corporation for US federal income tax purposes. As a result, the amount of cash available for distribution by the MLP would be reduced and the after-tax return to the Fund with respect to its investment in such MLPs would be materially reduced. Thus, if any of the MLPs owned by the Fund were treated as corporations for US federal income tax purposes, it could result in a reduction in the value of the Fund. Maturity Risk. Interest rate risk will generally affect the price of a fixed income security more if the security has a longer maturity. Fixed income securities with longer maturities will therefore be more volatile than other fixed income securities with shorter maturities. Conversely, fixed income securities with shorter maturities will be less volatile but generally provide lower potential returns than fixed income securities with longer maturities. The average maturity of the Fund's investments may affect the volatility of the Fund's share price. Non-Convertible Income Securities Risk. The Fund will also invest in non-convertible income securities. The Fund's investments in non-convertible income securities may have fixed or variable principal payments and all types of interest rate and dividend payment and reset terms, including fixed rate, adjustable rate, zero coupon, contingent, deferred, payment in kind and auction rate features. Recent events in the fixed-income markets, including the potential impact of the Federal Reserve Board tapering its quantitative easing program, may expose the Fund to heightened interest rate risk and volatility as a result of a rise in interest rates. In addition, the Fund is subject to the risk that interest rates may exhibit increased volatility, which could cause the Fund's net asset value ("NAV") to fluctuate more. A decrease in fixed-income market maker capacity may act to decrease liquidity in the fixed-income markets and act to further increase volatility, affecting the Fund's return. Non-US Government Obligation Risk. An investment in debt obligations of non-US governments and their political subdivisions involves special risks that are not present in corporate debt obligations. The non-US issuer of the sovereign debt or the non-US governmental authorities that control the repayment of the debt may be unable or unwilling to repay principal or interest when due, and the Fund may have limited recourse in the event of a default. During periods of economic uncertainty, the market prices of sovereign debt may be more volatile than prices of debt obligations of US issuers. Other Investment Companies (including ETFs) Risk. Investments in the securities of other investment companies, including ETFs, may involve duplication of advisory fees and certain other expenses. By investing in another investment company or ETF, the Fund becomes a shareholder thereof. As a result, Fund shareholders indirectly bear the Fund's proportionate share of the fees and expenses indirectly paid by shareholders of the other investment company or ETF, in addition to the fees and expenses Fund shareholders bear in connection with the Fund's own operations. If the investment company or ETF fails to achieve its investment objective, the value of the Fund's investment will decline, adversely affecting the Fund's performance. In addition, closed-end investment company and ETF shares potentially may trade at a discount or a premium and are subject to brokerage and other trading costs, which could result in greater expenses to the Fund. In addition, the Fund may engage in short sales of the securities of other investment companies. When the Fund shorts securities of another investment company, it borrows shares of that investment company which it then sells. The Fund closes out a short sale by purchasing the security that it has sold short and returning that security to the entity that lent the security. Portfolio Selection Risk. The value of your investment may decrease if the investment adviser's judgment about the attractiveness, value or market trends affecting a particular security, issuer, industry or sector or about market movements is incorrect. Portfolio Turnover Risk. The portfolio managers may actively and frequently trade securities or other instruments in the Fund's portfolio to carry out its investment strategies. A high portfolio turnover rate increases transaction costs, which may increase the Fund's expenses. Frequent and active trading may also cause adverse tax consequences for investors in the Fund due to an increase in short term capital gains. Preferred Share Liquidation Preference Risk. Preferred shares, if issued and outstanding, will be junior in liquidation and with respect to distribution rights to debt securities and any other borrowings. Senior securities representing indebtedness may constitute a substantial lien and burden on preferred shares by reason of their prior claim against our income and against our net assets in liquidation. The Fund may not be permitted to declare dividends or other distributions with respect to any series of preferred shares unless at such time the Fund meets applicable asset coverage requirements and the payment of principal or interest is not in default with respect to any borrowings. Recent Market Events. Since the 2008 financial crisis, financial markets throughout the world have experienced increased periods of volatility, depressed valuations, decreased liquidity and heightened uncertainty and turmoil. This turmoil resulted in unusual and extreme volatility in the equity and debt markets, in the prices of individual securities and in the world economy. Events that have contributed to these market conditions include, but are not limited to, major cybersecurity events, geopolitical events (such as wars (including Russia's military invasion of the Ukraine), terror attacks, natural or environmental disasters, country instability, and public health emergencies), measures to address budget deficits, downgrading of sovereign debt, declines in oil and commodity prices, dramatic changes in currency exchange rates, and public sentiment. In addition, many governments and quasi-governmental entities throughout the world have responded to the turmoil with a variety of significant fiscal and monetary policy changes, including, but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. The full extent of the political, economic and legal consequences of Brexit are not yet fully known, and the long-term impact of Brexit on the UK, the EU and the broader global economy may be significant. As a result of the political divisions within the UK and between the UK and the EU that the referendum vote has highlighted and the uncertain consequences of Brexit, the UK and European economies and the broader global economy could be significantly impacted, potentially resulting in increased market volatility and illiquidity, political, economic, and legal uncertainty, and lower economic growth for companies that rely significantly on Europe for their business activities and revenues. Any further exits from the EU, or the possibility of such exits, or the abandonment of the Euro, may cause additional market disruption globally and introduce new legal and regulatory uncertainties. In addition, policy and legislative changes in the United States and in other countries are changing many aspects of financial regulation. The impact of these changes on the markets, and the practical implications for market participants, may not be fully known for some time. Widespread disease and virus epidemics and pandemics, such as the coronavirus outbreak, could likewise be highly disruptive, adversely affecting individual companies, sectors, industries, markets, currencies, interest and inflation rates, credit ratings, investor sentiment, and other factors affecting the value of the Fund's investments. REIT Risk. Investing in real estate investment trusts ("REITs") involves certain unique risks in addition to those risks associated with investing in the real estate industry in general. An equity REIT may be affected by changes in the value of the underlying properties owned by the REIT. A mortgage REIT may be affected by changes in interest rates and the ability of the issuers of its portfolio mortgages to repay their obligations. REITs are dependent upon the skills of their managers and are not diversified. REITs are generally dependent upon maintaining cash flows to repay borrowings and to make distributions to shareholders and are subject to the risk of default by lessees or borrowers. REITs whose underlying assets are concentrated in properties used by a particular industry, such as health care, are also subject to risks associated with such industry. REITs (especially mortgage REITs) are also subject to interest rate risks. When interest rates decline, the value of a REIT's investment in fixed rate obligations can be expected to rise. Conversely, when interest rates rise, the value of a REIT's investment in fixed rate obligations can be expected to decline. If the REIT invests in adjustable rate mortgage loans the interest rates on which are reset periodically, yields on a REIT's investments in such loans will gradually align themselves to reflect changes in market interest rates. This causes the value of such investments to fluctuate less dramatically in response to interest rate fluctuations than would investments in fixed rate obligations. REITs may have limited financial resources, may utilize significant amounts of leverage, may trade less frequently and in a limited volume and may be subject to more abrupt or erratic price movements than larger company securities. Historically, REITs have been more volatile in price than the larger capitalization stocks included in Standard & Poor's 500 Stock Index. Risks Associated with Options (all Funds except CPZ). There are several risks associated with transactions in options. For example, there are significant differences between the securities markets and options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well- conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The Fund's ability to utilize options successfully will depend on Calamos' ability to predict pertinent market movements, which cannot be assured. The Fund may sell options on individual securities and securities indices. All call options sold by the Fund must be "covered." Even though the Fund will receive the option premium to help protect it against loss, a call option sold by the Fund exposes the Fund during the term of the option to possible loss of opportunity to realize appreciation in the market price of the underlying security or instrument and may require the Fund to hold a security or instrument that it might otherwise have sold. In addition, a loss on a call option sold may be greater than the premium received. The Fund may purchase and sell put options on individual securities and securities indices. In selling put options, there is a risk that the Fund may be required to buy the underlying security at a disadvantageous price above the market price. Risks Associated with Options (CPZ). The Fund may use options, including on the Fund's convertible securities or during the creation of synthetic convertible instruments. There are several risks associated with transactions in options. For example, there are significant differences between the securities markets and options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The Fund's ability to utilize options successfully will depend on Calamos' ability to predict pertinent market movements, which cannot be assured. The Fund intends to seek to generate income from option premiums by writing (selling) options. The Fund may write (sell) call options (i) on a portion of the equity securities (including securities that are convertible into equity securities) in the Fund's portfolio, (ii) on a portion of the equity securities the Fund has a right to receive upon conversion of a convertible security that it owns at the time it writes the call, and (iii) on broad-based securities indexes (such as the S&P 500 or MSCI EAFE) or certain ETFs that trade like common stocks but seek to replicate such market indexes. All call options sold by the Fund must be "covered", other than those sold in the Long/Short Component. For example, a call option written by the Fund will require the Fund to hold the securities subject to the call (or securities convertible into the needed securities without additional consideration) or to segregate cash or liquid assets sufficient to purchase and deliver the securities if the call is exercised. Even though the Fund will receive the option premium to help protect it against loss, a call option sold by the Fund exposes the Fund during the term of the option to possible loss of opportunity to realize appreciation in the market price of the underlying security or instrument and may require the Fund to hold a security or instrument that it might otherwise have sold. The Fund may purchase and sell put options on individual securities and securities indices. In selling put options, there is a risk that the Fund may be required to buy the underlying security at a disadvantageous price above the market price. A put option written by the Fund requires the Fund to segregate cash or liquid assets equal to the exercise price minus any margin the Fund is required to post. Rule 144A Securities Risk. The Fund may invest in securities that are issued and sold through transactions under Rule 144A of the Securities Act of 1933. Under the supervision and oversight of the Board of Trustees, Calamos will determine whether Rule 144A Securities are illiquid. If qualified institutional buyers are unwilling to purchase these Rule 144A Securities, the percentage of the Fund's assets invested in illiquid securities would increase. Typically, the Fund purchases Rule 144A Securities only if the Fund's adviser has determined them to be liquid. If any Rule 144A Security held by the Fund should become illiquid, the value of the security may be reduced and a sale of the security may be more difficult. Sector Risk. To the extent the Fund invests a significant portion of its assets in a particular sector, a greater portion of the Fund's performance may be affected by the general business and economic conditions affecting that sector. Each sector may share economic risk with the broader market, however there may be economic risks specific to each sector. As a result, returns from those sectors may trail returns from the overall stock market and it is possible that the Fund may underperform the broader market, or experience greater volatility. Short Selling Risk. The Fund will engage in short sales for investment and risk management purposes, including when the Adviser believes an investment will underperform due to a greater sensitivity to earnings growth of the issuer, default risk or interest rates. In times of unusual or adverse market, economic, regulatory or political conditions, the Fund may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions may exist for extended periods of time. Short sales are transactions in which the Fund sells a security or other instrument that it does not own but can borrow in the market. Short selling allows the Fund to profit from a decline in market price to the extent such decline exceeds the transaction costs and the costs of borrowing the securities and to obtain a low cost means of financing long investments that the Adviser believes are attractive. If a security sold short increases in price, the Fund may have to cover its short position at a higher price than the short sale price, resulting in a loss. The Fund will have substantial short positions and must borrow those securities to make delivery to the buyer under the short sale transaction. The Fund may not be able to borrow a security that it needs to deliver or it may not be able to close out a short position at an acceptable price and may have to sell related long positions earlier than it had expected. Thus, the Fund may not be able to successfully implement its short sale strategy due to limited availability of desired securities or for other reasons. Also, there is the risk that the counterparty to a short sale may fail to honor its contractual terms, causing a loss to the Fund. Generally, the Fund will have to pay a fee or premium to borrow securities and will be obligated to repay the lender of the security any dividends or interest that accrues on the security during the term of the loan. The amount of any gain from a short sale will be decreased, and the amount of any loss increased, by the amount of such fee, premium, dividends, interest or expense the Fund pays in connection with the short sale. Until the Fund replaces a borrowed security, it may be required to maintain a segregated account of cash or liquid assets with a broker or custodian to cover the Fund's short position. Generally, securities held in a segregated account cannot be sold unless they are replaced with other liquid assets. The Fund's ability to access the pledged collateral may also be impaired in the event the broker becomes bankrupt, insolvent or otherwise fails to comply with the terms of the contract. In such instances the Fund may not be able to substitute or sell the pledged collateral and may experience significant delays in obtaining any recovery in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in these circumstances. Additionally, the Fund must maintain sufficient liquid assets (less any additional collateral pledged to the broker), marked-to-market daily, to cover the borrowed securities obligations. This may limit the Fund's investment flexibility, as well as its ability to meet other current obligations. Because losses on short sales arise from increases in the value of the security sold short, such losses are theoretically unlimited. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security's value cannot decrease below zero. The Adviser's use of short sales in combination with long positions in the Fund's portfolio in an attempt to improve performance or reduce overall portfolio risk may not be successful and may result in greater losses or lower positive returns than if the Fund held only long positions. It is possible that the Fund's long securities positions will decline in value at the same time that the value of its short securities positions increase, thereby increasing potential losses to the Fund. In addition, the Fund's short selling strategies will limit its ability to fully benefit from increases in the fixed-income markets. By investing the proceeds received from selling securities short, the Fund could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Fund's exposure to long securities positions and make any change in the Fund's NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Fund employs will be successful during any period in which it is employed. Synthetic Convertible Instruments Risk. The value of a synthetic convertible instrument may respond differently to market fluctuations than a convertible instrument because a synthetic convertible instrument is composed of two or more separate securities, each with its own market value. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value. Synthetic convertible instruments created by other parties have the same attributes of a convertible security; however, the issuer of the synthetic convertible instrument assumes the credit risk associated with the investment, rather than the issuer of the underlying equity security into which the instrument is convertible. Investing in synthetic convertible instruments also involves the risk that the Fund does not achieve the investment exposure desired by Calamos. The Fund remains subject to the credit risk associated with the counterparty creating the synthetic convertible instrument. Tax Risk. The Fund may invest in certain securities, such as certain convertible securities and high yield securities, for which the federal income tax treatment may not be clear or may be subject to re-characterization by the Internal Revenue Service ("IRS"). It could be more difficult for the Fund to comply with certain federal income tax requirements applicable to regulated investment companies if the tax characterization of the Fund's investments is not clear or if the tax treatment of the income from such investments was successfully challenged by the IRS. In addition, the tax treatment of the Fund may be affected by future interpretations of the Internal Revenue Code of 1986, as amended and changes in the tax laws and regulations, all of which may apply with retroactive effect. US Government Security Risk. Some securities issued by US Government agencies or government sponsored enterprises are not backed by the full faith and credit of the US and may only be supported by the right of the agency or enterprise to borrow from the US Treasury. There can be no assurance that the US Government will always provide financial support to those agencies or enterprises. Volatility Risk. Risk may arise in connection with the use of derivative instruments from volatility of interest rates and the prices of reference instruments. Fund Level and Other Risks Currency Risk. To the extent that the Fund invests in securities or other instruments denominated in or indexed to foreign currencies, changes in currency exchange rates bring an added dimension of risk. Currency fluctuations could negatively impact investment gains or add to investment losses. Although the Fund may attempt to hedge against currency risk, the hedging instruments may not always perform as the Fund expects and could produce losses. Suitable hedging instruments may not be available for currencies of emerging market countries. The Fund's investment adviser may determine not to hedge currency risks, even if suitable instruments appear to be available. Cybersecurity Risk. Investment companies, such as the Fund, and their service providers are exposed to operational and information security risks resulting from cyberattacks, which may result in financial losses to a fund and its shareholders. Cyber-attacks include, among other behaviors, stealing or corrupting data maintained online or digitally, denial of service attacks on websites, "ransomware" that renders systems inoperable until ransom is paid, the unauthorized release of confidential information, or various other forms of cybersecurity breaches. Cyber-attacks affecting the Fund or the Adviser, custodian, transfer agent, distributor, administrator, intermediaries, trading counterparties, and other third-party service providers may adversely impact the Fund or the companies in which the Fund invests, causing the Fund's investments to lose value or to prevent a shareholder redemption or purchase from clearing in a timely manner. Inflation Risk. Inflation is the reduction in the purchasing power of money resulting from an increase in the price of goods and services. Inflation risk is the risk that the inflation adjusted or "real" value of an investment in preferred stock or debt securities or the income from that investment will be worth less in the future. As inflation occurs, the real value of the preferred stock or debt securities and the dividend payable to holders of preferred stock or interest payable to holders of debt securities declines. Leverage Risk (for all Funds except CPZ). The Fund has issued indebtedness and preferred shares and may borrow money or issue debt securities as permitted by the 1940 Act. As of October 31, 2023, the Fund has leverage in the form of borrowings under the SSB Agreement and outstanding MRP Shares. Leverage is the potential for the Fund to participate in gains and losses on an amount that exceeds the Fund's investment. The borrowing of money or issuance of debt securities and preferred shares represents the leveraging of the Fund's common shares. As a non-fundamental policy, the Fund may not issue preferred shares or borrow money and/or issue debt securities with an aggregate liquidation preference and aggregate principal amount exceeding 38% of the Fund's managed assets as measured at the time of borrowing or issuance of the new securities. However, the Board of Trustees reserves the right to issue preferred shares or debt securities or borrow to the extent permitted by the 1940 Act and the Fund's policies. Leverage creates risks which may adversely affect the return for the holders of common shares, including: • the likelihood of greater volatility in the NAV and market price of the Fund's common shares; • fluctuations in the dividend rates on any preferred shares borne by the Fund or in interest rates on borrowings and short-term debt; • increased operating costs, which are effectively borne by common shareholders, may reduce the Fund's total return; and • the potential for a decline in the value of an investment acquired with borrowed funds, while the Fund's obligations under such borrowing or preferred shares remain fixed. In addition, the rights of lenders and the holders of preferred shares and debt securities issued by the Fund will be senior to the rights of the holders of common shares with respect to the payment of dividends or to the payment of assets upon liquidation. Holders of preferred shares have voting rights in addition to and separate from the voting rights of common shareholders. The holders of preferred shares or debt, if any, on the one hand, and the holders of the common shares, on the other, may have interests that conflict in certain situations. Leverage is a speculative technique that could adversely affect the returns to common shareholders. Leverage can cause the Fund to lose money and can magnify the effect of any losses. To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the Fund's return will be greater than if leverage had not been used. Conversely, if the income or capital appreciation from the securities purchased with such funds is not sufficient to cover the cost of leverage or if the Fund incurs capital losses, the return of the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced or potentially eliminated. The Fund will pay, and common shareholders will effectively bear, any costs and expenses relating to any borrowings and to the issuance and ongoing maintenance of preferred shares or debt securities. Such costs and expenses include the higher management fee resulting from the use of any such leverage, offering and/or issuance costs, and interest and/or dividend expense and ongoing maintenance. These conditions may, directly or indirectly, result in higher leverage costs to common shareholders. Certain types of borrowings may result in the Fund being subject to covenants in credit agreements, including those relating to asset coverage, borrowing base and portfolio composition requirements and additional covenants that may affect the Fund's ability to pay dividends and distributions on common shares in certain instances. The Fund may also be required to pledge its assets to the lenders in connection with certain types of borrowings. The Fund may be subject to certain restrictions on investments imposed by guidelines of and covenants with rating agencies which may issue ratings for the preferred shares or short-term debt instruments issued by the Fund. These guidelines and covenants may impose asset coverage or portfolio composition requirements that are more stringent than those imposed by the 1940 Act. The Board of Trustees reserves the right to change the amount and type of leverage that the Fund uses, and reserves the right to implement changes to the Fund's borrowings that it believes are in the long-term interests of the Fund and its shareholders, even if such changes impose a higher interest rate or other costs or impacts over the intermediate, or short-term time period. There is no guarantee that the Fund will maintain leverage at the current rate, and the Board of Trustees reserves the right to raise, decrease, or eliminate the Fund's leverage exposure. If the Fund's ability to make dividends and distributions on its common shares is limited, such limitation could, under certain circumstances, impair the ability of the Fund to maintain its qualification for taxation as a regulated investment company or to reduce or eliminate tax at the Fund level, which would have adverse tax consequences for common shareholders. To the extent that the Fund is required, in connection with maintaining 1940 Act asset coverage requirements or otherwise, or elects to redeem any preferred shares or debt securities or prepay any borrowings, the Fund may need to liquidate investments to fund such redemptions or prepayments. Liquidation at times of adverse economic conditions may result in capital loss and reduce returns to common shareholders. Because Calamos' investment management fee is a percentage of the Fund's managed assets, Calamos' fee will be higher if the Fund is leveraged and Calamos will have an incentive to be more aggressive and leverage the Fund. Consequently, the Fund and Calamos may have differing interests in determining whether to leverage the Fund's assets. Any additional use of leverage by the Fund effected through new, additional or increased credit facilities or the issuance of preferred shares would require approval by the Board. In considering whether to approve the use of additional leverage, the Board would be presented with all relevant information necessary to make a determination whether or not additional leverage through those means would be in the best interests of the Fund, including information regarding any potential conflicts of interest. Leverage Risk (CPZ). The Fund anticipates that it will issue indebtedness and may issue preferred shares or borrow money or issue debt securities as permitted by the 1940 Act. As of October 31, 2023, the Fund has leverage in the form of borrowings under the SSB Agreement. Leverage is the potential for the Fund to participate in gains and losses on an amount that exceeds the Fund's investment. The borrowing of money or issuance of debt securities and preferred shares represents the leveraging of the Fund's common shares. As a non-fundamental policy, the Fund may not issue preferred shares or borrow money and issue debt securities with an aggregate liquidation preference and aggregate principal amount exceeding 38% of the Fund's total assets. However, the Board reserves the right to issue preferred shares or borrow to the extent permitted by the 1940 Act and the Fund's policies. Investments of short sale proceeds and economic leverage through derivatives are not counted as borrowings. Leverage creates risks which may adversely affect the return for the holders of common shares, including: • the likelihood of greater volatility in the NAV and market price of the Fund's common shares; • fluctuations in the interest rates on borrowings and short-term debt; • increased operating costs, which are effectively borne by common shareholders, may reduce the Fund's total return; and • the potential for a decline in the value of an investment acquired with borrowed funds, while the Fund's obligations under such borrowing remain fixed. The Fund's use of leverage is premised upon the expectation that the Fund's preferred share dividends or borrowing cost will be lower than the return the Fund achieves on its investments with the proceeds of the issuance of senior securities or borrowing. Such difference in return may result from the Fund's higher credit rating or the short-term nature of its borrowing compared to the lower credit quality, long-term nature of its investments. Because Calamos seeks to invest the Fund's managed assets (including the assets obtained from leverage) in a portfolio of potentially higher yielding investments or portfolio investments with the potential for capital appreciation, the holders of common shares will be the beneficiaries of the incremental return but will bear the risk of loss on investments made with the leverage proceeds. Should the differential between the Fund's return on investments made with the proceeds of leverage and the cost of the leverage narrow, the incremental return "pick up" will be reduced or the Fund may incur losses. Furthermore, if long-term interest rates rise without a corresponding increase in the yield on the Fund's portfolio investments or the Fund otherwise incurs losses on its investments, the Fund's NAV attributable to its common shares will reflect the decline in the value of portfolio holdings resulting therefrom. Leverage is a speculative technique that could adversely affect the returns to holders of common shares. Leverage can cause the Fund to lose money and can magnify the effect of any losses. To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the Fund's return will be greater than if leverage had not been used. Conversely, if the income or capital appreciation from the securities purchased with such funds is not sufficient to cover the cost of leverage or if the Fund incurs capital losses, the return of the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced or potentially eliminated. The Fund will pay, and common shareholders will effectively bear, any costs and expenses relating to any borrowings and to the issuance and ongoing maintenance of debt. Such costs and expenses include the higher management fee resulting from the use of any such leverage, offering and/or issuance costs, and interest expense and ongoing maintenance. These conditions may, directly or indirectly, result in higher leverage costs to common shareholders. Certain types of borrowings may result in the Fund being subject to covenants in credit agreements, including those relating to asset coverage, borrowing base and portfolio composition requirements and additional covenants that may affect the Fund's ability to pay dividends and distributions on common shares in certain instances. The Fund may also be required to pledge its assets to the lenders in connection with certain types of borrowings. The Fund may be subject to certain restrictions on investments imposed by guidelines of rating agencies which may issue ratings for the short-term debt instruments issued by the Fund. These guidelines may impose asset coverage or portfolio composition requirements that are more stringent than those imposed by the 1940 Act. If the Fund's ability to make dividends and distributions on its common shares is limited, such limitation could, under certain circumstances, impair the ability of the Fund to maintain its qualification for taxation as a regulated investment company or to reduce or eliminate tax at the Fund level, which would have adverse tax consequences for common shareholders. To the extent that the Fund is required, in connection with maintaining 1940 Act asset coverage requirements or otherwise, or elects to redeem any senior securities or prepay any borrowings, the Fund may need to liquidate investments to fund such redemptions or prepayments. Liquidation at times of adverse economic conditions may result in capital loss and reduce returns to common shareholders. Because Calamos' investment management fee is a percentage of the Fund's managed assets, Calamos' fee will be higher if the Fund is leveraged and Calamos will have an incentive to be more aggressive and leverage the Fund. Consequently, the Fund and Calamos may have differing interests in determining whether to leverage the Fund's assets. Any additional use of leverage by the Fund would require approval by the Board. In considering whether to approve the use of additional leverage, the Board would be presented with all relevant information necessary to make a determination whether or not additional leverage would be in the best interests of the Fund, including information regarding any potential conflicts of interest. Limited Term Risk. Unless the limited term provision of the Fund's Declaration of Trust is amended by shareholders in accordance with the Declaration of Trust, or unless the Fund completes the Eligible Tender Offer and converts to perpetual existence, the Fund will dissolve on the Dissolution Date. The Fund is not a so called "target date" or "life cycle" fund whose asset allocation becomes more conservative over time as its target date, often associated with retirement, approaches. In addition, the Fund is not a "target term" fund whose investment objective is to return its original NAV on the Dissolution Date. The Fund's investment objective and policies are not designed to seek to return to investors that purchase Shares in this offering their initial investment of $20.00 per Share on the Dissolution Date or in the Eligible Tender Offer, and such investors and investors that purchase Shares after the completion of this offering may receive more or less than their original investment upon dissolution or in the Eligible Tender Offer. Because the assets of the Fund will be liquidated in connection with the dissolution, the Fund will incur transaction costs in connection with dispositions of portfolio securities. The Fund does not limit its investments to securities having a maturity date prior to the Dissolution Date and may be required to sell portfolio securities when it otherwise would not, including at times when market conditions are not favorable, which may cause the Fund to lose money. In particular, the Fund's portfolio may still have large exposures to illiquid securities as the Dissolution Date approaches, and losses due to portfolio liquidation may be significant. During the winddown period, beginning one year before the Dissolution Date, the Fund may begin liquidating all or a portion of the Fund's portfolio, and may deviate from its investment policies and may not achieve its investment objective. During the wind-down period, the Fund's portfolio composition may change as more of its portfolio holdings are called or sold and portfolio holdings are disposed of in anticipation of dissolution. The disposition of portfolio investments by the Fund could cause market prices of such instruments, and hence the NAV and market price of the Shares, to decline. In addition, disposition of portfolio investments will cause the Fund to incur increased brokerage and related transaction expenses. The Fund may receive proceeds from the disposition of portfolio investments that are less than the valuations of such investments by the Fund. Rather than reinvesting the proceeds of matured, called or sold securities, the Fund may invest such proceeds in short term or other lower yielding securities or hold the proceeds in cash, which may adversely affect its performance and the market price of the Shares. The Fund may distribute the proceeds in one or more liquidating distributions prior to the final liquidation, which may cause fixed expenses to increase when expressed as a percentage of assets under management. Upon dissolution, it is anticipated that the Fund will have distributed substantially all of its net assets to Shareholders, although securities for which no market exists or securities trading at depressed prices, if any, may be placed in a liquidating trust. Shareholders will bear the costs associated with establishing and maintaining a liquidating trust, if necessary. Securities placed in a liquidating trust may be held for an indefinite period of time until they can be sold or pay out all of their cash flows. The Fund cannot predict the amount, if any, of securities that will be required to be placed in a liquidating trust. If the Fund conducts the Eligible Tender Offer, the Fund anticipates that funds to pay the aggregate purchase price of Shares accepted for purchase pursuant to the tender offer will be first derived from any cash on hand and then from the proceeds from the sale of portfolio investments held by the Fund. In addition, the Fund may be required to dispose of portfolio investments in connection with any reduction in the Fund's outstanding leverage necessary in order to maintain the Fund's desired leverage ratios following a tender offer. The risks related to the disposition of securities in connection with the Fund's dissolution also would be present in connection with the disposition of securities in connection with the Eligible Tender Offer. It is likely that during the pendency of a tender offer, and possibly for a time thereafter, the Fund will hold a greater than normal percentage of its total assets in cash and cash equivalents, which may impede the Fund's ability to achieve its investment objective and decrease returns to Shareholders. If the Fund's tax basis for the investments sold is less than the sale proceeds, the Fund will recognize capital gains, which the Fund will generally distribute to Shareholders. In addition, the Fund's purchase of tendered Shares pursuant to a tender offer will have tax consequences for tendering Shareholders and may have tax consequences for non-tendering Shareholders. The purchase of Shares by the Fund pursuant to a tender offer will have the effect of increasing the proportionate interest in the Fund of non-tendering Shareholders. All Shareholders remaining after a tender offer will be subject to proportionately higher expenses due to the reduction in the Fund's total assets resulting from payment for the tendered Shares. Such reduction in the Fund's total assets may also result in less investment flexibility, reduced diversification and greater volatility for the Fund, and may have an adverse effect on the Fund's investment performance. The Fund is not required to conduct the Eligible Tender Offer. If the Fund conducts the Eligible Tender Offer, there can be no assurance that the number of tendered Shares would not result in the Fund's net assets totaling less than the Dissolution Threshold, in which case the Eligible Tender Offer will be terminated, no Shares will be repurchased pursuant to the Eligible Tender Offer and the Fund will dissolve on the Dissolution Date (subject to possible extensions). Following the completion of the Eligible Tender Offer in which the number of tendered Shares would result in the Fund's net assets totaling greater than the Dissolution Threshold, the Board may eliminate the Dissolution Date upon the affirmative vote of a majority of the Board and without a Shareholder vote. Thereafter, the Fund will have a perpetual existence. The Adviser may have a conflict of interest in recommending to the Board that the Dissolution Date be eliminated and the Fund have a perpetual existence. The Fund is not required to conduct additional tender offers following the Eligible Tender Offer and conversion to perpetual existence. Therefore, remaining Shareholders may not have another opportunity to participate in a tender offer. Shares of closed-end management investment companies frequently trade at a discount from their NAV, and as a result remaining Shareholders may only be able to sell their Shares at a discount to NAV. Loan Risk. The Fund may invest in loans which may not be (i) rated at the time of investment, (ii) registered with the SEC or (iii) listed on a securities exchange. There may not be as much public information available regarding these loans as is available for other Fund investments, such as exchange-listed securities. As well, there may not be an active trading market for some loans, meaning they may be illiquid and more difficult to value than other more liquid securities. Settlement periods for loans are longer than for exchange traded securities, typically ranging between 1 and 3 weeks, and in some cases much longer. There is no central clearinghouse for loan trades, and the loan market has not established enforceable settlement standards or remedies for failure to settle. Because the interest rates of floating-rate loans in which the Fund may invest may reset frequently, if market interest rates fall, the loans' interest rates will be reset to lower levels, potentially reducing the Fund's income. Because the adviser may wish to invest in the publicly traded securities of an obligor, the Fund may not have access to material non-public information regarding the obligor to which other investors have access Market Discount Risk. The Fund's common shares have traded both at a premium and at a discount relative to NAV. Common shares of closed-end investment companies frequently trade at a discount from NAV, but in some cases trade above NAV. The risk of the Fund's common shares trading at a discount is a risk separate from the risk of a decline in the Fund's NAV as a result of investment activities. The Fund's NAV may be reduced immediately following an offering by the offering costs for common shares or other securities, which will be borne entirely by all common shareholders. The Fund's common shares are designed primarily for long-term investors, and you should not purchase common shares if you intend to sell them shortly after purchase. Whether shareholders will realize a gain or loss upon the sale of the Fund's common shares depends upon whether the market value of the shares at the time of sale is above or below the price the shareholder paid, taking into account transaction costs for the shares, and is not directly dependent upon the Fund's NAV. Because the market value of the Fund's common shares will be determined by factors such as the relative demand for and supply of the shares in the market, general market conditions and other factors beyond the control of the Fund, the Fund cannot predict whether its common shares will trade at, below or above the Fund's NAV, or below or above the public offering price for the common shares. Market Disruption Risk. Certain events have a disruptive effect on the securities markets, such as terrorist attacks, war and other geopolitical events, earthquakes, storms and other disasters. The Fund cannot predict the effects of similar events in the future on the US economy or any foreign economy. Market Impact Risk. The sale of the Fund's common shares (or the perception that such sales may occur) may have an adverse effect on prices in the secondary market for the Fund's common shares. An increase in the number of common shares available may put downward pressure on the market price for the Fund's common shares. These sales also might make it more difficult for the Fund to sell additional equity securities in the future at a time and price the Fund deems appropriate. Ratings and Asset Coverage Risk. To the extent that senior securities are rated, a rating does not eliminate or necessarily mitigate the risks of investing in the Fund's senior securities, and a rating may not fully or accurately reflect all of the credit and market risks associated with that senior security. A rating agency could downgrade the rating of the Fund's shares of preferred stock or debt securities, which may make such securities less liquid in the secondary market, though potentially with higher resulting interest rates. If a rating agency downgrades the rating assigned to a senior security, the Fund may alter its portfolio or redeem the senior security. The Fund may voluntarily redeem senior securities under certain circumstances Reduction of Leverage Risk. A Fund may take action to reduce the amount of leverage it employs. Reduction of the leverage employed by the Fund, including by redemption of preferred shares (if applicable), will in turn reduce the amount of assets available for investment in portfolio securities. This reduction in leverage may negatively impact the Fund's financial performance, including the Fund's ability to sustain current levels of distributions on common shares. The Board reserves the right to change the amount and type of leverage that the Fund uses, and reserves the right to implement changes to the Fund's borrowings that it believes are in the best long-term interests of the Fund and its shareholders, even if such changes impose a higher interest rate or other costs or impacts over the intermediate, or short-term time period. There is no guarantee that the Fund will maintain leverage at the current rate, and the Board reserves the right to raise, decrease, or eliminate the Fund's leverage exposure. Regulatory Risk. The enforceability of agreements underlying hedging transactions may depend on compliance with applicable statutory and other regulatory requirements and, depending on the identity of the counterparty, applicable international requirements. New or amended regulations may be imposed by the CFTC, the SEC, the Federal Reserve or other financial regulators, other governmental regulatory authorities or self-regulatory organizations that supervise the financial markets that could adversely affect the Fund. In particular, these agencies are empowered to promulgate a variety of new rules pursuant to recently enacted financial reform legislation in the United States. The Fund also may be adversely affected by changes in the enforcement or interpretation of existing statues and rules by these governmental regulatory authorities or self-regulatory organizations. In addition, the securities and futures markets are subject to comprehensive statutes, regulations and margin requirements. For instance, the Dodd-Frank Wall Street Reform and Consumer Protection Act ("Dodd-Frank Act") could have an adverse effect on the Fund's ability to use derivative instruments. The Dodd-Frank Act is designed to impose stringent regulation on the over-the-counter derivatives market in an attempt to increase transparency and accountability and provides for, among other things, new clearing, execution, margin, reporting, recordkeeping, business conduct, disclosure, position limit, minimum net capital and registration requirements. Although the CFTC has released final rules relating to clearing, execution, reporting, risk management, compliance, position limit, anti-fraud, consumer protection, portfolio reconciliation, documentation, recordkeeping, business conduct, margin requirements and registration requirements under the Dodd-Frank Act, many of the provisions are subject to further final rulemaking, and thus the Dodd-Frank Act's ultimate impact remains unclear. New regulations could, among other things, restrict the Fund's ability to engage in derivatives transactions (for example, by making certain types of derivatives transactions no longer available to our funds), increase the costs of using these instruments (for example, by increasing margin, capital or reporting requirements) and/or make them less effective and, as a result, the Fund may be unable to execute its investment strategy. Limits or restrictions applicable to the counterparties with which the Fund engages in derivative transactions could also prevent the Fund from using these instruments, affect the pricing or other factors relating to these instruments or may change availability of certain investments. It is unclear how the regulatory changes will affect counterparty risk. Secondary Market Risk. The market value of exchange-listed preferred shares that the Fund may issue will be determined by factors such as the relative demand for and supply of the preferred shares in the market, general market conditions and other factors beyond the control of the Fund. It may be difficult to predict the trading patterns of preferred shares, including the effective costs of trading. There is a risk that the market for preferred shares may be thinly traded and relatively illiquid compared to the market for other types of securities. Senior Leverage Risk. Preferred shares will be junior in liquidation and with respect to distribution rights to debt securities and any other borrowings. Senior securities representing indebtedness may constitute a substantial lien and burden on preferred shares by reason of their prior claim against the Fund's income and against the Fund's net assets in liquidation. The Fund may not be permitted to declare dividends or other distributions with respect to any series of preferred shares unless at such time the Fund meets applicable asset coverage requirements and the payment of principal or interest is not in default with respect to any borrowings. |  |  |  |  |  |  |  |  |  |  |  |
Effects of Leverage [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Effects of Leverage The SSB Agreement provides for credit availability for the Fund, such that it may borrow up to $430 million. As of October 31, 2023, the Fund had utilized $314 million of the $430 million available under the SSB Agreement ($260 million of advances outstanding, and $54 million in structural leverage consisting of collateral received from counterparties via State Street Bank and Trust Company in connection with securities on loan), representing 28.1% of the Fund's managed assets as of that date, and had $133 million of MRP Shares outstanding, representing 11.9% of the Fund's managed assets. Combined, the borrowings under the SSB Agreement and the outstanding MRP Shares represented 39.9% of the Fund's managed assets. Interest on the SSB Agreement was charged on the drawn amount at the rate of the Overnight Bank Financing Rate ("OBFR") plus 0.80%, payable monthly in arrears, from November 1, 2022, through June 30, 2023. The rate from July 1, 2023, through October 31, 2023, was OBFR plus 0.52%. Interest on overdue amounts or interest on the drawn amount paid during an event of default was charged OBFR plus 2.80% from November 1, 2022, through June 30, 2023. The rate from July 1, 2023, through October 31, 2023, was charged at OBFR plus 2.52%. These rates represent floating rates of interest that may change over time. The SSB Agreement has a commitment fee of 0.10% of any undrawn amount. As of October 31, 2023, the interest rate charged under the SSB Agreement was 5.84%. The Fund's MRP Shareholders are entitled to receive monthly cash dividends, at a currently effective dividend rate per annum for each series of MRP Shares as follows (subject to adjustment as described in the Fund's prospectus): 4.00% for Series B MRP Shares, 4.24% for Series C MRP Shares, 2.45% for Series D MRP Shares, and 2.68% for Series E MRP Shares. To cover the interest expense on the borrowings under the SSB Agreement (including "net income" payments made with respect to borrowings offset by collateral for securities on loan) and the dividend payments associated with the MRP Shares, based on rates in effect on October 31, 2023, the Fund's portfolio would need to experience an annual return of 2.06% (before giving effect to expenses associated with senior securities). The following table illustrates the hypothetical effect on the return to a holder of the Fund's common shares of the leverage obtained by us (and utilized on October 31, 2023). The purpose of this table is to assist you in understanding the effects of leverage. As the table shows, leverage generally increases the return to common shareholders when portfolio return is positive and greater than the cost of leverage and decreases the return when the portfolio return is negative or less than the cost of leverage. The figures appearing in the table are hypothetical and actual returns may be greater or less than those appearing in the table.
Assumed Portfolio Return (Net of Expenses) |  |  | (10.00 | )% |  |  | (5.00 | )% |  |  | 0.00 | % |  |  | 5.00 | % |  |  | 10.00 | % |
Corresponding Common Share Return(1)​ |  |  | (20.13 | )% |  |  | (11.78 | )% |  |  | (3.43 | )% |  |  | 4.92 | % |  |  | 13.27 | % |
(1)​ Includes interest expense on the borrowings under the SSB Agreement, accrued at interest rates in effect on October 31, 2023 of 5.84%, and dividend expense on the MRP Shares. |  |  |  |  |  |  |  |  |  |  |  |
Annual Dividend Payment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (1.14) |  | $ (1.14) | $ (1.1) |  | $ (0.96) | $ (0.96) | $ (1.13) | $ (1.14) | $ (1.14) | $ (1.14) | $ (1.14) |
Effects of Leverage [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assumed Portfolio Return (Net of Expenses) |  |  | (10.00 | )% |  |  | (5.00 | )% |  |  | 0.00 | % |  |  | 5.00 | % |  |  | 10.00 | % |
Corresponding Common Share Return(1)​ |  |  | (20.13 | )% |  |  | (11.78 | )% |  |  | (3.43 | )% |  |  | 4.92 | % |  |  | 13.27 | % |
(1)​ Includes interest expense on the borrowings under the SSB Agreement, accrued at interest rates in effect on October 31, 2023 of 5.84%, and dividend expense on the MRP Shares. |  |  |  |  |  |  |  |  |  |  |  |
Return at Minus Ten [Percent] | [8] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (20.13%) |  |  |  |  |  |  |  |  |  |  |  |
Return at Minus Five [Percent] | [8] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (11.78%) |  |  |  |  |  |  |  |  |  |  |  |
Return at Zero [Percent] | [8] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (3.43%) |  |  |  |  |  |  |  |  |  |  |  |
Return at Plus Five [Percent] | [8] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.92% |  |  |  |  |  |  |  |  |  |  |  |
Return at Plus Ten [Percent] | [8] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13.27% |  |  |  |  |  |  |  |  |  |  |  |
Effects of Leverage, Purpose [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The following table illustrates the hypothetical effect on the return to a holder of the Fund's common shares of the leverage obtained by us (and utilized on October 31, 2023). The purpose of this table is to assist you in understanding the effects of leverage. As the table shows, leverage generally increases the return to common shareholders when portfolio return is positive and greater than the cost of leverage and decreases the return when the portfolio return is negative or less than the cost of leverage. The figures appearing in the table are hypothetical and actual returns may be greater or less than those appearing in the table. |  |  |  |  |  |  |  |  |  |  |  |
Share Price [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Market and Net Asset Value Information Our common shares have traded both at a premium and a discount to NAV. We cannot predict whether our shares will trade in the future at a premium or discount to NAV. The provisions of the 1940 Act generally require that the public offering price of common shares (less any underwriting commissions and discounts) must equal or exceed the NAV per share of a company's common stock (calculated within 48 hours of pricing). Our issuance of common shares may have an adverse effect on prices in the secondary market for our common shares by increasing the number of common shares available, which may put downward pressure on the market price for our common shares. Shares of common stock of closed-end investment companies frequently trade at a discount from NAV. The following table sets forth for each of the periods indicated the high and low closing market prices for our common shares on Nasdaq, the NAV per share and the premium or discount to NAV per share at which our common shares were trading. NAV is shown for the last business day of each quarter. See "Net Asset Value" for information as to the determination of our NAV.
|  | MARKET PRICE(1)​ |  | NET ASSET VALUE AT QUARTER |  | PREMIUM/ (DISCOUNT) TO NET ASSET VALUE(3)​ |
QUARTER ENDED |  | HIGH |  | LOW |  | END(2)​ |  | HIGH |  | LOW |
October 31, 2023 |  | $ | 11.32 |  |  | $ | 10.00 |  |  | $ | 8.99 |  |  |  | 15.20 | % |  |  | 4.56 | % |
July 31, 2023 |  | $ | 11.36 |  |  | $ | 9.90 |  |  | $ | 10.51 |  |  |  | 10.21 | % |  |  | 1.53 | % |
April 30, 2023 |  | $ | 12.34 |  |  | $ | 10.21 |  |  | $ | 9.94 |  |  |  | 16.91 | % |  |  | 1.49 | % |
January 31, 2023 |  | $ | 12.09 |  |  | $ | 10.51 |  |  | $ | 10.61 |  |  |  | 15.03 | % |  |  | 3.89 | % |
October 31, 2022 |  | $ | 12.90 |  |  | $ | 9.66 |  |  | $ | 10.25 |  |  |  | 14.01 | % |  |  | -3.36 | % |
July 31, 2022 |  | $ | 13.00 |  |  | $ | 10.17 |  |  | $ | 11.18 |  |  |  | 16.28 | % |  |  | -2.33 | % |
April 30, 2022 |  | $ | 14.50 |  |  | $ | 11.81 |  |  | $ | 12.05 |  |  |  | 4.69 | % |  |  | -4.58 | % |
January 31, 2022 |  | $ | 16.34 |  |  | $ | 12.96 |  |  | $ | 13.62 |  |  |  | 4.21 | % |  |  | -4.14 | % |
October 31, 2021 |  | $ | 15.90 |  |  | $ | 14.93 |  |  | $ | 15.49 |  |  |  | 3.31 | % |  |  | -0.20 | % |
July 31, 2021 |  | $ | 15.45 |  |  | $ | 14.01 |  |  | $ | 15.05 |  |  |  | 1.25 | % |  |  | -1.34 | % |
April 30, 2021 |  | $ | 15.32 |  |  | $ | 13.65 |  |  | $ | 15.33 |  |  |  | -1.54 | % |  |  | -8.08 | % |
January 31, 2021 |  | $ | 14.13 |  |  | $ | 10.94 |  |  | $ | 15.07 |  |  |  | -9.19 | % |  |  | -12.97 | % |
Source: Fund Accounting Records (1)​ Based on high and low closing market price per share during the respective quarter and does not reflect commissions. (2)​ Based on the NAV calculated on the close of business on the last business day of each calendar quarter. (3)​ Premium and discount information is shown for the days when the Fund experienced its high and low closing market prices, respectively, per share during the respective quarter. |  |  |  |  |  |  |  |  |  |  |  |
Lowest Price or Bid | [9] | $ 10 |  | $ 9.9 |  | $ 10.21 |  | $ 10.51 |  | $ 9.66 | $ 10.17 |  | $ 11.81 |  | $ 12.96 |  | $ 14.93 |  | $ 14.01 |  | $ 13.65 |  | $ 10.94 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Highest Price or Bid | [9] | $ 11.32 |  | $ 11.36 |  | $ 12.34 |  | $ 12.09 |  | $ 12.9 | $ 13 |  | $ 14.5 |  | $ 16.34 |  | $ 15.9 |  | $ 15.45 |  | $ 15.32 |  | $ 14.13 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Highest Price or Bid, Premium (Discount) to NAV [Percent] | [10] | 15.20% |  | 10.21% |  | 16.91% |  | 15.03% |  | 14.01% | 16.28% |  | 4.69% |  | 4.21% |  | 3.31% |  | 1.25% |  | (1.54%) |  | (9.19%) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lowest Price or Bid, Premium (Discount) to NAV [Percent] | [10] | 4.56% |  | 1.53% |  | 1.49% |  | 3.89% |  | (3.36%) | (2.33%) |  | (4.58%) |  | (4.14%) |  | (0.20%) |  | (1.34%) |  | (8.08%) |  | (12.97%) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Price |  | $ 9.99 |  |  |  |  |  |  |  | $ 10.78 |  |  |  |  |  |  | $ 15.81 |  |  |  |  |  |  |  | $ 9.99 |  | 10.78 | 15.81 |  | 10.89 | 10.67 | 9.91 | 11.59 | 9.89 | 10.41 | 13.69 |
NAV Per Share |  | $ 8.99 | [11] | $ 10.51 | [11] | $ 9.94 | [11] | $ 10.61 | [11] | $ 10.26 | $ 11.18 | [11] | $ 12.05 | [11] | $ 13.62 | [11] | $ 15.49 | [11] | $ 15.05 | [11] | $ 15.33 | [11] | $ 15.07 | [11] | $ 8.99 | [11] | $ 10.26 | $ 15.49 | [11] | $ 12.54 | $ 10.64 | $ 10.46 | $ 11.35 | $ 10.73 | $ 11.68 | $ 13.45 | $ 13.2
Capital Stock, Long-Term Debt, and Other Securities [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long Term Debt [Table Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Note 7 – Notes Payable The Funds have each entered into an Amended and Restated Liquidity Agreement (the "SSB Agreement") with State Street Bank and Trust Company ("SSB") that allows each Fund to borrow up to a certain limit as shown in the table below, as well as engage in securities lending and securities repurchase transactions.
FUND |  | BORROWING LIMIT (IN MILLIONS) |
Convertible Opportunities and Income Fund |  | $ | 430.0 |  |
Convertible and High Income Fund |  |  | 480.0 |  |
Strategic Total Return Fund |  |  | 1,130.0 |  |
Dynamic Convertible and Income Fund |  |  | 370.0 |  |
Global Dynamic Income Fund |  |  | 265.0 |  |
Global Total Return Fund |  |  | 55.0 |  |
Long/Short Equity & Dynamic Income Trust |  |  | 150.0 |  |
Advances under the SSB Agreement are secured by assets of the Funds that are held with the Funds' custodian in a separate account (the "pledged collateral"). Interest on the SSB Agreement was charged on the drawn amount at the rate of OBFR plus 0.80% from November 1, 2022 through June 30, 2023. The rate from July 1, 2023 through October 31, 2023 was OBFR plus 0.52%. A commitment fee of 0.10% is payable on any undrawn balance. For the year ended October 31, 2023, the Funds borrowed according to the table below:
FUND |  | AVERAGE BORROWINGS (IN MILLIONS) |  | AVERAGE INTEREST RATE |  | TOTAL OUTSTANDING BORROWINGS (IN MILLIONS) |  | INTEREST RATE APPLICABLE TO BORROWINGS |
Convertible Opportunities and Income Fund |  | $ | 323.6 |  |  |  | 5.35 | % |  | $ | 314.4 |  |  |  | 5.65 | % |
Convertible and High Income Fund |  |  | 349.6 |  |  |  | 5.34 | % |  |  | 340.4 |  |  |  | 5.64 | % |
Strategic Total Return Fund |  |  | 800.5 |  |  |  | 5.36 | % |  |  | 800.5 |  |  |  | 5.64 | % |
Dynamic Convertible and Income Fund |  |  | 217.4 |  |  |  | 5.32 | % |  |  | 210.0 |  |  |  | 5.62 | % |
Global Dynamic Income Fund |  |  | 109.0 |  |  |  | 5.36 | % |  |  | 130.6 |  |  |  | 5.64 | % |
Global Total Return Fund |  |  | 25.0 |  |  |  | 5.31 | % |  |  | 30.1 |  |  |  | 5.60 | % |
Long/Short Equity & Dynamic Income Trust |  |  | 120.0 |  |  |  | 5.41 | % |  |  | 120.0 |  |  |  | 5.69 | %
Under the terms of the SSB Agreement, all securities lent through SSB must be secured continuously by collateral received in cash. Cash collateral received by SSB on behalf of the Fund is deposited by SSB in a custodial account of the Fund and then applied to repay borrowings under the SSB, such that the cash advanced to the Fund remains unchanged. Upon termination of a securities loan, SSB will advance to the Fund the cash collateral required to be returned by the Fund, or secure the appropriate amount through one or more securities lending transactions as the Fund's agent, and deposit the amount to a custodial account of the Fund and then subsequently return such amount to the securities borrower against return of the securities on loan. Again, the net cash to the Fund is unaltered. Only the composition of the advance is changed, and regardless of the composition of advances as between cash collateral for securities lending transactions or borrowings from SSB, they are not reflected separately in the Statement of Assets and Liabilities but as a component of the Notes Payable. The Fund has the right to recall securities which have been lent at any time. The securities lending arrangement with SSB involves characteristics common in arm's length relationships in which one party may benefit at the expense of the other party. As of October 31, 2023, the Funds had securities on loan under the SSB Agreement which are reflected in the Investment in securities, at value on the Statement of Assets and Liabilities and are shown in the table below. The borrowings are categorized as Level 2 within the fair value hierarchy. The composition of the securities on loan was as follows:
FUND |  | SECURITIES ON LOAN (IN MIILIONS) |  | FIXED INCOME SECURITIES (IN MILLIONS) |  | EQUITY SECURITIES (IN MILLIONS) |
Convertible Opportunities and Income Fund |  | $ | 52.9 |  |  | $ | 40.8 |  |  | $ | 12.1 |  |
Convertible and High Income Fund |  |  | 48.1 |  |  |  | 40.1 |  |  |  | 8.0 |  |
Strategic Total Return Fund |  |  | 721.1 |  |  |  | 80.8 |  |  |  | 640.3 |  |
Dynamic Convertible and Income Fund |  |  | 15.0 |  |  |  | 9.2 |  |  |  | 5.8 |  |
Global Dynamic Income Fund |  |  | 14.0 |  |  |  | 3.4 |  |  |  | 10.6 |  |
Global Total Return Fund |  |  | 5.7 |  |  |  | 1.2 |  |  |  | 4.5 |  |
Long/Short Equity & Dynamic Income Trust |  |  | 2.1 |  |  |  | 1.4 |  |  |  | 0.7
Long Term Debt, Structuring [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The Funds have each entered into an Amended and Restated Liquidity Agreement (the "SSB Agreement") with State Street Bank and Trust Company ("SSB") that allows each Fund to borrow up to a certain limit as shown in the table below, as well as engage in securities lending and securities repurchase transactions.
FUND |  | BORROWING LIMIT (IN MILLIONS) |
Convertible Opportunities and Income Fund |  | $ | 430.0 |  |
Convertible and High Income Fund |  |  | 480.0 |  |
Strategic Total Return Fund |  |  | 1,130.0 |  |
Dynamic Convertible and Income Fund |  |  | 370.0 |  |
Global Dynamic Income Fund |  |  | 265.0 |  |
Global Total Return Fund |  |  | 55.0 |  |
Long/Short Equity & Dynamic Income Trust |  |  | 150.0 |  |
Advances under the SSB Agreement are secured by assets of the Funds that are held with the Funds' custodian in a separate account (the "pledged collateral"). Interest on the SSB Agreement was charged on the drawn amount at the rate of OBFR plus 0.80% from November 1, 2022 through June 30, 2023. The rate from July 1, 2023 through October 31, 2023 was OBFR plus 0.52%. A commitment fee of 0.10% is payable on any undrawn balance. For the year ended October 31, 2023, the Funds borrowed according to the table below:
FUND |  | AVERAGE BORROWINGS (IN MILLIONS) |  | AVERAGE INTEREST RATE |  | TOTAL OUTSTANDING BORROWINGS (IN MILLIONS) |  | INTEREST RATE APPLICABLE TO BORROWINGS |
Convertible Opportunities and Income Fund |  | $ | 323.6 |  |  |  | 5.35 | % |  | $ | 314.4 |  |  |  | 5.65 | % |
Convertible and High Income Fund |  |  | 349.6 |  |  |  | 5.34 | % |  |  | 340.4 |  |  |  | 5.64 | % |
Strategic Total Return Fund |  |  | 800.5 |  |  |  | 5.36 | % |  |  | 800.5 |  |  |  | 5.64 | % |
Dynamic Convertible and Income Fund |  |  | 217.4 |  |  |  | 5.32 | % |  |  | 210.0 |  |  |  | 5.62 | % |
Global Dynamic Income Fund |  |  | 109.0 |  |  |  | 5.36 | % |  |  | 130.6 |  |  |  | 5.64 | % |
Global Total Return Fund |  |  | 25.0 |  |  |  | 5.31 | % |  |  | 30.1 |  |  |  | 5.60 | % |
Long/Short Equity & Dynamic Income Trust |  |  | 120.0 |  |  |  | 5.41 | % |  |  | 120.0 |  |  |  | 5.69 | %
Long Term Debt, Dividends and Covenants [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Under the terms of the SSB Agreement, all securities lent through SSB must be secured continuously by collateral received in cash. Cash collateral received by SSB on behalf of the Fund is deposited by SSB in a custodial account of the Fund and then applied to repay borrowings under the SSB, such that the cash advanced to the Fund remains unchanged. Upon termination of a securities loan, SSB will advance to the Fund the cash collateral required to be returned by the Fund, or secure the appropriate amount through one or more securities lending transactions as the Fund's agent, and deposit the amount to a custodial account of the Fund and then subsequently return such amount to the securities borrower against return of the securities on loan. Again, the net cash to the Fund is unaltered. Only the composition of the advance is changed, and regardless of the composition of advances as between cash collateral for securities lending transactions or borrowings from SSB, they are not reflected separately in the Statement of Assets and Liabilities but as a component of the Notes Payable. The Fund has the right to recall securities which have been lent at any time. The securities lending arrangement with SSB involves characteristics common in arm's length relationships in which one party may benefit at the expense of the other party. As of October 31, 2023, the Funds had securities on loan under the SSB Agreement which are reflected in the Investment in securities, at value on the Statement of Assets and Liabilities and are shown in the table below. The borrowings are categorized as Level 2 within the fair value hierarchy. The composition of the securities on loan was as follows:
FUND |  | SECURITIES ON LOAN (IN MIILIONS) |  | FIXED INCOME SECURITIES (IN MILLIONS) |  | EQUITY SECURITIES (IN MILLIONS) |
Convertible Opportunities and Income Fund |  | $ | 52.9 |  |  | $ | 40.8 |  |  | $ | 12.1 |  |
Convertible and High Income Fund |  |  | 48.1 |  |  |  | 40.1 |  |  |  | 8.0 |  |
Strategic Total Return Fund |  |  | 721.1 |  |  |  | 80.8 |  |  |  | 640.3 |  |
Dynamic Convertible and Income Fund |  |  | 15.0 |  |  |  | 9.2 |  |  |  | 5.8 |  |
Global Dynamic Income Fund |  |  | 14.0 |  |  |  | 3.4 |  |  |  | 10.6 |  |
Global Total Return Fund |  |  | 5.7 |  |  |  | 1.2 |  |  |  | 4.5 |  |
Long/Short Equity & Dynamic Income Trust |  |  | 2.1 |  |  |  | 1.4 |  |  |  | 0.7
American Depositary Receipts Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | American Depositary Receipts Risk. The stocks of most foreign companies that trade in the US markets are traded as ADRs. US depositary banks issue these stocks. Each ADR represents one or more shares of foreign stock or a fraction of a share. The price of an ADR corresponds to the price of the foreign stock in its home market, adjusted to the ratio of the ADRs to foreign company shares. Therefore, while purchasing a security on a US exchange, the risks inherently associated with foreign investing still apply to ADRs. |  |  |  |  |  |  |  |  |  |  |  |
Antitakeover Provisions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Antitakeover Provisions. The Fund's Agreement and Declaration of Trust and By-Laws include provisions that could limit the ability of other entities or persons to acquire control of the Fund or to change the composition of its Board of Trustees. Such provisions could limit the ability of shareholders to sell their shares at a premium over prevailing market prices by discouraging a third party from seeking to obtain control of the Fund. These provisions include staggered terms of office for the Trustees, advance notice requirements for shareholder proposals, and super-majority voting requirements for certain transactions with affiliates, converting the Fund to an open-end investment company or a merger, asset sale or similar transaction. Holders of preferred shares have voting rights in addition to and separate from the voting rights of common shareholders with respect to certain of these matters. Holders of any preferred shares, voting separately as a single class, have the right to elect at least two Trustees at all times. The holders of preferred shares or debt, if any, on the one hand, and the holders of the common shares, on the other, may have interests that conflict with each other in certain situations, including conflicts that relate to the fees and expenses of the Fund. |  |  |  |  |  |  |  |  |  |  |  |
Cash Holdings Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Cash Holdings Risk. To the extent the Fund holds cash positions, the Fund risks achieving lower returns and potential lost opportunities to participate in market appreciation which could negatively impact the Fund's performance and ability to achieve its investment objective. |  |  |  |  |  |  |  |  |  |  |  |
Contingent Liabilities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Contingent Liabilities Risk. Entering into derivative contracts in order to pursue the Fund's various hedging strategies could require the Fund to fund cash payments in the future under certain circumstances, including an event of default or other early termination event, or the decision by a counterparty to request margin in the form of securities or other forms of collateral under the terms of the derivative contract or applicable laws. The amounts due with respect to a derivative contract would generally be equal to the unrealized loss of the open positions with the respective counterparty and could also include other fees and charges. These payments are contingent liabilities and therefore may not appear on the Fund's balance sheet. The Fund's ability to fund these contingent liabilities will depend on the liquidity of the Fund's assets and access to capital at the time, and the need to fund these contingent liabilities could adversely impact the Fund's financial condition. |  |  |  |  |  |  |  |  |  |  |  |
Convertible Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Convertible Securities Risk. The value of a convertible security is influenced by both the yield of non- convertible securities of comparable issuers and by the value of the underlying common stock. The value of a convertible security viewed without regard to its conversion feature (i.e., strictly on the basis of its yield) is sometimes referred to as its "investment value." A convertible security's investment value tends to decline as prevailing interest rate levels increase. Conversely, a convertible security's investment value tends to increase as prevailing interest rate levels decline. |  |  |  |  |  |  |  |  |  |  |  |
Counterparty And Settlement Risk All Funds Except C P Z [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Counterparty and Settlement Risk (all Funds except CPZ). Trading options, futures contracts, swaps and other derivative financial instruments entails credit risk with respect to the counterparties with whom and through which the Fund trades. Such instruments when traded over the counter do not include the same protections as may apply to trading derivatives on organized Calamos—We note that CPZ includes a more robust version of this risk disclosure. We think it is appropriate to include this version as well. exchanges. Substantial losses may arise from the insolvency, bankruptcy or default of a counterparty and risk of settlement default of parties with whom the Fund trades securities. This risk may be heightened during volatile market conditions. Settlement mechanisms in emerging markets are generally less developed and reliable than those in more developed countries, thus increasing the risks. In the past, broker-dealers and other financial institutions have experienced extreme financial difficulty, sometimes resulting in bankruptcy of the institution. Although Calamos monitors the creditworthiness of the Fund's counterparties, there can be no assurance that the Fund's counterparties will not experience similar difficulties, possibly resulting in losses to the Fund. If a counterparty becomes bankrupt, or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a bankruptcy or other reorganization proceeding. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances. Material exposure to a single or small group of counterparties increases the Fund's counterparty risk. |  |  |  |  |  |  |  |  |  |  |  |
Counterparty And Settlement Risk C P Z [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Counterparty and Settlement Risk (CPZ). Trading options, futures contracts, swaps and other derivative financial instruments entails credit risk with respect to the counterparties with whom and through which the Fund trades. Such instruments when traded over the counter do not include the same protections as may apply to trading derivatives on organized exchanges. Substantial losses may arise from the insolvency, bankruptcy or default of a counterparty and risk of settlement default of parties with whom the Fund trades securities. This risk may be heightened during volatile market conditions. Settlement mechanisms in emerging markets are generally less developed and reliable than those in more developed countries, thus increasing the risks. Counterparty risk is the risk that the other party in a derivative transaction will not fulfill its contractual obligation. Changes in the credit quality of the Fund's counterparties with respect to its derivative transactions may affect the value of those instruments. By entering into derivatives, the Fund assumes the risk that its counterparties could experience financial hardships that could call into question their continued ability to perform their obligations. As a result, concentrations of such derivatives in any one counterparty would subject the Fund to an additional degree of risk with respect to defaults by such counterparty. |  |  |  |  |  |  |  |  |  |  |  |
Covenant Lite Loans Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | "Covenant-Lite" Loans Risk. Some of the loans in which the Fund may invest may be "covenant-lite" loans, which means the loans contain fewer or no maintenance covenants than other loans and do not include terms which allow the lender to monitor the performance of the borrower and declare a default if certain criteria are breached. The Fund may experience delays in enforcing its rights on its holdings of covenant-lite loans. However, a convertible security's market value tends to reflect the market price of the common stock of the issuing company when that stock price is greater than the convertible security's "conversion price." The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security and changes in interest rates. Thus, the convertible security may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities would be paid before the company's common stockholders. If a counterparty becomes bankrupt or otherwise fails to perform its obligations under a derivative contract due to financial difficulties, such bankruptcy or failure to perform is likely to result in a default under such derivative contract, unless such default is cured. Default by a party with whom the Fund enters into a hedging transaction may result in the loss of unrealized profits, leaving the Fund with unsecured exposure and force the Fund to cover its resale commitments, if any, at the then current market price. It may not always be possible to dispose of or close out a hedging position without the consent of the hedging counterparty, and the Fund may not be able to enter into an offsetting contract in order to cover its risk. The Fund cannot assure its shareholders that a liquid secondary market will exist for hedging instruments purchased or sold, and the Fund may be required to maintain a position until exercise or expiration, which could result in losses. Furthermore, upon the bankruptcy of a counterparty, the Fund may experience significant delays in obtaining any recovery under the derivative contract in a dissolution, assignment for the benefit of creditors, liquidation, winding-up, bankruptcy, or other analogous proceeding. In addition, in the event of the insolvency of a counterparty to a derivative transaction, the derivative transaction would typically be terminated at its fair market value. If the Fund is owed this fair market value in the termination of the derivative transaction and its claim is unsecured, the Fund will be treated as a general creditor of such counterparty, and will not have any claim with respect to the underlying security. The Fund may obtain only a limited recovery or may obtain no recovery in such circumstances and the enforceability of agreements for hedging transactions may depend on compliance with applicable statutory and other regulatory requirements and, depending on the identity of the counterparty, applicable international requirements. Certain interest rate and credit default swaps are subject to mandatory clearing, in which case a central clearing counterparty stands between each buyer and seller and effectively guarantees performance of each derivative contract, to the extent of its available resources for such purpose. As a result, the counterparty risk is now shifted from bilateral risk between the parties to the individual credit risk of the central clearing counterparty and the futures commission merchant through which the Fund holds its cleared position. Even in such case, there can be no assurance that a clearing house, or its members, will satisfy the clearing house's obligations to the Fund. Uncleared derivatives have no such protection; each party bears the risk that its direct counterparty will default. |  |  |  |  |  |  |  |  |  |  |  |
Credit Risks [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Credit Risk. An issuer of a fixed income security could be downgraded or default. If the Fund holds securities that have been downgraded, or that default on payment, the Fund's performance could be negatively affected. |  |  |  |  |  |  |  |  |  |  |  |
Debt Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Debt Securities Risk. The Fund may invest in debt securities, including corporate bonds and high yield securities. In addition to the risks described elsewhere in the Fund's prospectus (such as high yield securities risk and interest rate risk), debt securities are subject to certain additional risks, including issuer risk and reinvestment risk. Issuer risk is the risk that the value of debt securities may decline for a number of reasons which directly relate to the issuer, such as management performance, leverage and reduced demand for the issuer's goods and services. Reinvestment risk is the risk that income from the Fund's portfolio will decline if the Fund invests the proceeds from matured, traded or called bonds at market interest rates that are below the Fund portfolio's current earnings rate. A decline in income could affect the market price of the Fund's common shares or the overall return of the Fund. |  |  |  |  |  |  |  |  |  |  |  |
Decline In Net Asset Value Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Decline in Net Asset Value Risk. A material decline in the Fund's NAV may impair the Fund's ability to maintain required levels of asset coverage for any outstanding borrowings or any debt securities or preferred shares. |  |  |  |  |  |  |  |  |  |  |  |
Default Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Default Risk. Default risk refers to the risk that a company that issues a convertible or debt security will be unable to fulfill its obligations to repay principal and interest. The lower a debt security is rated, the greater its default risk. As a result, the Fund may incur cost and delays in enforcing its rights against the defaulting issuer. |  |  |  |  |  |  |  |  |  |  |  |
Derivatives Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Derivatives Risk. Generally, derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index, and may relate to individual debt or equity instruments, interest rates, currencies or currency exchange rates, commodities, related indexes and other assets. The Fund may utilize a variety of derivative instruments including, but not limited to, interest rate swaps, caps, and floors, convertible securities, synthetic convertible instruments, options on individual securities, index options, long calls, covered calls, long puts, cash-secured short puts and protective puts for hedging, risk management and investment purposes. The Fund's use of derivative instruments involves investment risks and transaction costs to which the Fund would not be subject absent the use of these instruments and, accordingly, may result in losses greater than if they had not been used. The use of derivative instruments may have risks including, among others, leverage risk, duration mismatch risk, correlation risk, liquidity risk, interest rate risk, volatility risk, credit risk, management risk and counterparty risk. Derivatives also involve the risk of mispricing or improper valuation and the risk that changes in the value of a derivative may not correlate perfectly with an underlying asset, interest rate or index. Suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Fund will engage in these transactions to reduce exposure to other risks when that would be beneficial. Furthermore, the skills needed to employ derivatives strategies are different from those needed to select portfolio securities and, in connection with such strategies, the Fund makes predictions with respect to market conditions, liquidity, currency movements, market values, interest rates and other applicable factors, which may be inaccurate. Thus, the use of derivative instruments may require the Fund to sell or purchase portfolio securities at inopportune times or for prices below or above the current market values, may limit the amount of appreciation the Fund can realize on an investment or may cause the Fund to hold a security that it might otherwise want to sell. Tax rules governing the Fund's transactions in derivative instruments may also affect whether gains and losses recognized by the Fund are treated as ordinary or capital, accelerate the recognition of income or gains to the Fund, defer losses to the Fund, and cause adjustments in the holding periods of the Fund's securities, thereby affecting, among other things, whether capital gains and losses are treated as short-term or long-term. These rules could therefore affect the amount, timing and/or character of distributions to shareholders. In addition, there may be situations in which the Fund elects not to use derivative instruments that result in losses greater than if they had been used. Amounts paid by the Fund as premiums and cash or other assets held in margin accounts with respect to the Fund's derivative instruments would not be available to the Fund for other investment purposes, which may result in lost opportunities for gain. Derivative instruments can be illiquid, may disproportionately increase losses and may have a potentially large impact on Fund performance. |  |  |  |  |  |  |  |  |  |  |  |
Diminished Voting Power And Excess Cash Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Diminished Voting Power and Excess Cash Risk. The voting power of current shareholders will be diluted to the extent that such shareholders do not purchase shares in any future common share offerings or do not purchase sufficient shares to maintain their percentage interest. In addition, if the Fund is unable to invest the proceeds of such offering as intended, its per share distribution may decrease (or may consist of return of capital) and the Fund may not participate in market advances to the same extent as if such proceeds were fully invested as planned. |  |  |  |  |  |  |  |  |  |  |  |
Duration Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Duration Risk. Duration measures the time-weighted expected cash flows of a fixed-income security, which can determine its sensitivity to changes in the general level of interest rates. The value of securities with longer durations tend to be more sensitive to interest rate changes than securities with shorter durations. The longer the Fund's dollar-weighted average duration, the more its value can generally be expected to be sensitive to interest rate changes than a fund with a shorter dollar-weighted average duration. Duration differs from maturity in that it considers a security's coupon payments in addition to the amount of time until the security matures. Various techniques may be used to shorten or lengthen the Fund's duration. As the value of a security changes over time, so will its duration. |  |  |  |  |  |  |  |  |  |  |  |
Early Redemption Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Early Redemption Risk. The Fund may voluntarily redeem preferred shares or may be forced to redeem preferred shares to meet regulatory requirements and the asset coverage requirements of the preferred shares. Such redemptions may be at a time that is unfavorable to holders of the preferred shares |  |  |  |  |  |  |  |  |  |  |  |
Emerging Markets Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Emerging Markets Risk. Emerging market countries may have relatively unstable governments and economies based on only a few industries, which may cause greater instability. The value of emerging market securities will likely be particularly sensitive to changes in the economies of such countries. These countries are also more likely to experience higher levels of inflation, deflation or currency devaluations, which could adversely affect the value of the Fund's investments and hurt those countries' economies and securities markets. Securities issued in these countries may be more volatile and less liquid than securities issued in foreign countries with more developed economies or markets. Loss may also result from the imposition of exchange controls, confiscations and other government restrictions, or from problems in share registration, settlement, custody, or other operational risks. |  |  |  |  |  |  |  |  |  |  |  |
Equity Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Equity Securities Risk. Equity investments are subject to greater fluctuations in market value than other asset classes as a result of such factors as the issuer's business performance, investor perceptions, stock market trends and general economic conditions. Equity securities are subordinated to bonds and other debt instruments in a company's capital structure in terms of priority to corporate income and liquidation payments. The Fund may invest in preferred stocks and convertible securities of any rating, including below investment grade. Below investment grade securities or comparable unrated securities are considered predominantly speculative with respect to the issuer's ability to pay interest and principal and are susceptible to default or decline in market value due to adverse economic and business developments. The market values for below investment grade securities tend to be very volatile, and these securities are generally less liquid than investment- grade debt securities. For these reasons, your investment in the Fund is subject to the following specific risks: • increased price sensitivity to changing interest rates and to a deteriorating economic environment; • greater risk of loss due to default or declining credit quality; • adverse company specific events are more likely to render the issuer unable to make interest and/or principal payments; and • if a negative perception of the below investment grade market develops, the price and liquidity of below investment grade securities may be depressed. This negative perception could last for a significant period of time. |  |  |  |  |  |  |  |  |  |  |  |
Foreign Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Foreign Securities Risk. Investments in non-US issuers may involve unique risks compared to investing in securities of US issuers. These risks are more pronounced to the extent that the Fund invests a significant portion of its non-US investments in one region or in the securities of emerging market issuers. These risks may include: • less information may be available about non-US issuers or markets due to less rigorous disclosure or accounting standards or regulatory practices in foreign jurisdictions; • many non-US markets are smaller, less liquid and more volatile. In a changing market, Calamos may not be able to sell the Fund's portfolio securities at times, in amounts and at prices it considers reasonable; • an adverse effect of currency exchange rate changes or controls on the value of the Fund's investments; • the economies of non-US countries may grow at slower rates than expected or may experience a downturn or recession; • economic, political and social developments may adversely affect the securities markets in foreign jurisdictions, including expropriation and nationalization; • the difficulty in obtaining or enforcing a court judgment in non-US countries; • restrictions on foreign investments in non-US jurisdictions; • difficulties in effecting the repatriation of capital invested in non-US countries; • withholding and other non-US taxes may decrease the Fund's return; • the ability for the Public Company Accounting Oversight Board, which regulates auditors of US public companies, is unable to inspect audit work papers in certain foreign countries; • often limited rights and few practical remedies to pursue shareholder claims, including class actions or fraud claims, and the ability of the Commission, the US Department of Justice and other authorities to bring and enforce actions against foreign issuers or foreign persons is limited; and • dividend income the Fund receives from foreign securities may not be eligible for the special tax treatment applicable to qualified dividend income. Based upon the Fund's test for determining whether an issuer is a "foreign issuer", it is possible that an issuer of securities in which the Fund invests could be organized under the laws of a foreign country, yet still conduct a substantial portion of its business in the US or have substantial assets in the US. In this case, such a "foreign issuer" may be subject to the market conditions in the US to a greater extent than it may be subject to the market conditions in the country of its organization. There may be less publicly available information about non-US markets and issuers than is available with respect to US securities and issuers. Non-US companies generally are not subject to accounting, auditing and financial reporting standards, practices and requirements comparable to those applicable to US companies. The trading markets for most non-US securities are generally less liquid and subject to greater price volatility than the markets for comparable securities in the United States. The markets for securities in certain emerging markets are in the earliest stages of their development. Even the markets for relatively widely traded securities in certain non-US markets, including emerging market countries, may not be able to absorb, without price disruptions, a significant increase in trading volume or trades of a size customarily undertaken by institutional investors in the United States. Additionally, market making and arbitrage activities are generally less extensive in such markets, which may contribute to increased volatility and reduced liquidity. Economies and social and political conditions in individual countries may differ unfavorably from those in the United States. Non-US economies may have less favorable rates of growth of gross domestic product, rates of inflation, currency valuation, capital reinvestment, resource self-sufficiency and balance of payments positions. Many countries have experienced substantial, and in some cases extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, very negative effects on the economies and securities markets of certain emerging countries. Unanticipated political or social developments may also affect the values of the Fund's investments and the availability to the Fund of additional investments in such countries. |  |  |  |  |  |  |  |  |  |  |  |
Forward Currency Exchange Contracts Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Forward Currency Exchange Contracts Risk. Forward contracts are contractual agreements to purchase or sell a specified currency at a specified future date (or within a specified time period) at a price set at the time of the contract. The Fund may not fully benefit from, or may lose money on, forward currency exchange transactions if changes in currency exchange rates do not occur as anticipated or do not correspond accurately to changes in the value of the Fund's holdings. |  |  |  |  |  |  |  |  |  |  |  |
Geographic Concentration Risks [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Geographic Concentration Risk. Investments in a particular country or geographic region may be particularly susceptible to political, diplomatic or economic conditions and regulatory requirements. To the extent the Fund concentrates its investments in a particular country, region or group of regions, the Fund may be more volatile than a more geographically diversified fund. |  |  |  |  |  |  |  |  |  |  |  |
High Yield Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | High Yield Securities Risk. The Fund may invest in high yield securities of any rating. Investment in high yield securities involves substantial risk of loss. Below investment grade non-convertible debt securities or comparable unrated securities are commonly referred to as "junk bonds" and are considered predominantly speculative with respect to the issuer's ability to pay interest and principal and are susceptible to default or decline in market value due to adverse economic and business developments. The market values for high yield securities tend to be very volatile, and these securities are less liquid than investment grade debt securities. For these reasons, your investment in the Fund is subject to the following specific risks: • increased price sensitivity to changing interest rates and to a deteriorating economic environment; • greater risk of loss due to default or declining credit quality; • adverse company specific events are more likely to render the issuer unable to make interest and/or principal payments; and • if a negative perception of the high yield market develops, the price and liquidity of high yield securities may be depressed. This negative perception could last for a significant period of time. Adverse changes in economic conditions are more likely to lead to a weakened capacity of a high yield issuer to make principal payments and interest payments than an investment grade issuer. The principal amount of high yield securities outstanding has proliferated in the past decade as an increasing number of issuers have used high yield securities for corporate financing. An economic downturn could severely affect the ability of highly leveraged issuers to service their debt obligations or to repay their obligations upon maturity. The Fund may incur additional expenses to the extent it is required to seek recovery upon a default in payment of principal or interest on its portfolio holdings. In certain circumstances, the Fund may be required to foreclose on an issuer's assets and take possession of its property or operations. In such circumstances, the Fund would incur additional costs in disposing of such assets and potential liabilities from operating any business acquired. The secondary market for high yield securities may not be as liquid as the secondary market for more highly rated securities, a factor which may have an adverse effect on the Fund's ability to dispose of a particular security. There are fewer dealers in the market for high yield securities than for investment grade obligations. The prices quoted by different dealers may vary significantly and the spread between the bid and asked price is generally much larger than for higher quality instruments. Under adverse market or economic conditions, the secondary market for high yield securities could contract further, independent of any specific adverse changes in the condition of a particular issuer, and these instruments may become illiquid. As a result, the Fund could find it more difficult to sell these securities or may be able to sell the securities only at prices lower than if such securities were widely traded. Prices realized upon the sale of such lower rated or unrated securities, under these circumstances, may be less than the prices used in calculating the Fund's NAV. |  |  |  |  |  |  |  |  |  |  |  |
Interest Rate Risks [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Interest Rate Risk. In addition to the risks described above, debt securities, including high yield securities, are subject to certain risks, including: • if interest rates go up, the value of debt securities in the Fund's portfolio generally will decline; • during periods of declining interest rates, the issuer of a security may exercise its option to prepay principal earlier than scheduled, forcing the Fund to reinvest in lower yielding securities. This is known as call or prepayment risk. Debt securities frequently have call features that allow the issuer to repurchase the security prior to its stated maturity. An issuer may redeem an obligation if the issuer can refinance the debt at a lower cost due to declining interest rates or an improvement in the credit standing of the issuer; • during periods of rising interest rates, the average life of certain types of securities may be extended because of slower than expected principal payments. This may lock in a below market interest rate, increase the estimated period until the security is paid in full and reduce the value of the security. This is known as extension risk; • rising interest rates could result in an increase in the cost of the Fund's leverage and could adversely affect the ability of the Fund to meet asset coverage requirements with respect to leverage; • variable rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. When the Fund holds variable rate securities, a decrease in market interest rates will adversely affect the income received from such securities and the NAV of the Fund's shares; and • to the extent the Federal Reserve Board continues to raise interest rates, there is a risk that interest rates across the financial system may also rise. Increases in volatility and interest rates in the fixed-income market may expose the Fund to heightened interest rate risk. |  |  |  |  |  |  |  |  |  |  |  |
Interest Rate Transactions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Interest Rate Transactions Risk. The Fund may enter into an interest rate swap, cap or floor transaction to attempt to protect itself from increasing dividend or interest expenses on its leverage resulting from increasing short-term interest rates and to hedge its portfolio securities. A decline in interest rates may result in a decline in the value of the swap or cap, which may result in a decline in the NAV of the Fund. Depending on the state of interest rates in general, the Fund's use of interest rate swap or cap transactions could enhance or harm the overall performance of the common shares. To the extent there is a decline in interest rates, the value of the interest rate swap or cap could decline and could result in a decline in the NAV of the common shares. In addition, if the counterparty to an interest rate swap or cap defaults, the Fund would not be able to use the anticipated net receipts under the swap or cap to offset the dividend or interest payments on the Fund's leverage or offset certain losses in its portfolio. Depending on whether the Fund would be entitled to receive net payments from the counterparty on the swap or cap, which in turn would depend on the general state of short-term interest rates at that point in time, such a default could negatively impact the performance of the common shares. In addition, at the time an interest rate swap or cap transaction reaches its scheduled termination date, there is a risk that the Fund would not be able to obtain a replacement transaction or that the terms of the replacement would not be as favorable as on the expiring transaction. If either of these events occurs, it could have a negative impact on the performance of the common shares. If the Fund fails to maintain a required 200% asset coverage of the liquidation value of any outstanding preferred shares or if the Fund loses its rating on its preferred shares or fails to maintain other covenants with respect to the preferred shares, the Fund may be required to redeem some or all of the preferred shares. Similarly, the Fund could be required to prepay the principal amount of any debt securities or other borrowings. Such redemption or prepayment would likely result in the Fund seeking to terminate early all or a portion of any swap or cap transaction. Early termination of a swap could result in a termination payment by or to the Fund. Early termination of a cap could result in a termination payment to the Fund. The Fund intends to segregate with its custodian cash or liquid securities having a value at least equal to the Fund's net payment obligations under any swap transaction, marked-to-market daily. Currently, certain categories of interest rate swaps are subject to mandatory clearing, and more are expected to be cleared in the future. The counterparty risk for cleared derivatives is generally lower than for uncleared OTC derivative transactions because generally a clearing organization becomes substituted for each counterparty to a cleared derivative contract and, in effect, guarantees the parties' performance under the contract as each party to a trade looks only to the clearing house for performance of financial obligations. However, there can be no assurance that a clearing house, or its members, will satisfy the clearing house's obligations to the Fund. |  |  |  |  |  |  |  |  |  |  |  |
Liquidity Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Liquidity Risk. The Fund may invest without limit in securities that, at the time of investment, are illiquid (i.e., any investment that the Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment). The Fund may also invest without limit in Rule 144A Securities determined to be liquid. Calamos, under the supervision and oversight of the Board of Trustees, will determine whether Rule 144A Securities are illiquid (that is, not readily marketable). Illiquid securities may be difficult to dispose of at a fair price at the times when the Fund believes it is desirable to do so. Investment of the Fund's assets in illiquid securities may restrict the Fund's ability to take advantage of market opportunities. The market price of illiquid securities generally is more volatile than that of more liquid securities, which may adversely affect the price that the Fund pays for or recovers upon the sale of illiquid securities. Illiquid securities are also more difficult to value and may be fair valued in which case Calamos' judgment may play a greater role in the valuation process. The risks associated with illiquid securities may be particularly acute in situations in which the Fund's operations require cash and could result in the Fund borrowing to meet its short-term needs or incurring losses on the sale of illiquid securities. The Fund may also invest without limitation in securities that have not been registered for public sale, but that are eligible for purchase and sale by certain qualified institutional buyers. |  |  |  |  |  |  |  |  |  |  |  |
Management Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Management Risk. Calamos' judgment about the attractiveness, relative value or potential appreciation of a particular sector, security or investment strategy may prove to be incorrect. |  |  |  |  |  |  |  |  |  |  |  |
Master Limited Partnerships Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Master Limited Partnerships Risk. Investments in MLPs involve risks that differ from investments in common stock. Holders of MLP common units are subject to certain risks inherent in the structure of MLPs, including (i) tax risks, (ii) risk related to limited control of management or the general partner or managing member, (iii) limited rights to vote on matters affecting the MLP, except with respect to extraordinary transactions, (iv) conflicts of interest between the general partner or managing member and its affiliates, on the one hand, and the limited partners or members, on the other hand, including those arising from incentive distribution payments or corporate opportunities, and (v) cash flow risks. MLP common units and other equity securities can be affected by macro-economic and other factors affecting the stock market in general, expectations of interest rates, investor sentiment towards MLPs or the energy sector, changes in a particular issuer's financial condition, or unfavorable or unanticipated poor performance of a particular issuer (in the case of MLPs, generally measured in terms of distributable cash flow). Prices of common units of individual MLPs and other equity securities also can be affected by fundamentals unique to the partnership or company, including cash flow growth, cash generating power and distribution coverage. Although certain MLPs may trade on national securities exchanges, certain MLPs may trade less frequently than those of larger companies due to their market capitalizations. Due to limited trading volumes of certain MLPs, the prices of such MLPs may display abrupt or erratic movements at times. Additionally, it may be more difficult for the Fund to buy and sell significant amounts of such securities without an unfavorable impact on prevailing market prices. The Fund's investment in securities that are less actively traded or over time experience decreased trading volume may restrict its ability to dispose of the securities at a fair price. Such a situation may prevent the Fund from limiting losses or realizing gains. This also may adversely affect the Fund's ability to make dividend distributions to shareholders. MLPs are generally treated as partnerships for US federal income tax purposes. Partnerships do not pay US federal income tax at the partnership level. Rather, each partner is allocated a share of the partnership's income, gains, losses, deductions and expenses. A change in current tax law, or a change in the business of a given MLP, could result in an MLP being treated as a corporation for US federal income tax purposes. As a result, the amount of cash available for distribution by the MLP would be reduced and the after-tax return to the Fund with respect to its investment in such MLPs would be materially reduced. Thus, if any of the MLPs owned by the Fund were treated as corporations for US federal income tax purposes, it could result in a reduction in the value of the Fund. |  |  |  |  |  |  |  |  |  |  |  |
Maturity Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Maturity Risk. Interest rate risk will generally affect the price of a fixed income security more if the security has a longer maturity. Fixed income securities with longer maturities will therefore be more volatile than other fixed income securities with shorter maturities. Conversely, fixed income securities with shorter maturities will be less volatile but generally provide lower potential returns than fixed income securities with longer maturities. The average maturity of the Fund's investments may affect the volatility of the Fund's share price. |  |  |  |  |  |  |  |  |  |  |  |
Non Convertible Income Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Non-Convertible Income Securities Risk. The Fund will also invest in non-convertible income securities. The Fund's investments in non-convertible income securities may have fixed or variable principal payments and all types of interest rate and dividend payment and reset terms, including fixed rate, adjustable rate, zero coupon, contingent, deferred, payment in kind and auction rate features. Recent events in the fixed-income markets, including the potential impact of the Federal Reserve Board tapering its quantitative easing program, may expose the Fund to heightened interest rate risk and volatility as a result of a rise in interest rates. In addition, the Fund is subject to the risk that interest rates may exhibit increased volatility, which could cause the Fund's net asset value ("NAV") to fluctuate more. A decrease in fixed-income market maker capacity may act to decrease liquidity in the fixed-income markets and act to further increase volatility, affecting the Fund's return. |  |  |  |  |  |  |  |  |  |  |  |
Non U S Government Obligation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Non-US Government Obligation Risk. An investment in debt obligations of non-US governments and their political subdivisions involves special risks that are not present in corporate debt obligations. The non-US issuer of the sovereign debt or the non-US governmental authorities that control the repayment of the debt may be unable or unwilling to repay principal or interest when due, and the Fund may have limited recourse in the event of a default. During periods of economic uncertainty, the market prices of sovereign debt may be more volatile than prices of debt obligations of US issuers. |  |  |  |  |  |  |  |  |  |  |  |
Portfolio Selection Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Portfolio Selection Risk. The value of your investment may decrease if the investment adviser's judgment about the attractiveness, value or market trends affecting a particular security, issuer, industry or sector or about market movements is incorrect. |  |  |  |  |  |  |  |  |  |  |  |
Portfolio Turnover Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Portfolio Turnover Risk. The portfolio managers may actively and frequently trade securities or other instruments in the Fund's portfolio to carry out its investment strategies. A high portfolio turnover rate increases transaction costs, which may increase the Fund's expenses. Frequent and active trading may also cause adverse tax consequences for investors in the Fund due to an increase in short term capital gains. |  |  |  |  |  |  |  |  |  |  |  |
Recent Market Events Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Recent Market Events. Since the 2008 financial crisis, financial markets throughout the world have experienced increased periods of volatility, depressed valuations, decreased liquidity and heightened uncertainty and turmoil. This turmoil resulted in unusual and extreme volatility in the equity and debt markets, in the prices of individual securities and in the world economy. Events that have contributed to these market conditions include, but are not limited to, major cybersecurity events, geopolitical events (such as wars (including Russia's military invasion of the Ukraine), terror attacks, natural or environmental disasters, country instability, and public health emergencies), measures to address budget deficits, downgrading of sovereign debt, declines in oil and commodity prices, dramatic changes in currency exchange rates, and public sentiment. In addition, many governments and quasi-governmental entities throughout the world have responded to the turmoil with a variety of significant fiscal and monetary policy changes, including, but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. The full extent of the political, economic and legal consequences of Brexit are not yet fully known, and the long-term impact of Brexit on the UK, the EU and the broader global economy may be significant. As a result of the political divisions within the UK and between the UK and the EU that the referendum vote has highlighted and the uncertain consequences of Brexit, the UK and European economies and the broader global economy could be significantly impacted, potentially resulting in increased market volatility and illiquidity, political, economic, and legal uncertainty, and lower economic growth for companies that rely significantly on Europe for their business activities and revenues. Any further exits from the EU, or the possibility of such exits, or the abandonment of the Euro, may cause additional market disruption globally and introduce new legal and regulatory uncertainties. In addition, policy and legislative changes in the United States and in other countries are changing many aspects of financial regulation. The impact of these changes on the markets, and the practical implications for market participants, may not be fully known for some time. Widespread disease and virus epidemics and pandemics, such as the coronavirus outbreak, could likewise be highly disruptive, adversely affecting individual companies, sectors, industries, markets, currencies, interest and inflation rates, credit ratings, investor sentiment, and other factors affecting the value of the Fund's investments. |  |  |  |  |  |  |  |  |  |  |  |
Investing In Real Estate Investment Trusts Risk Reit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | REIT Risk. Investing in real estate investment trusts ("REITs") involves certain unique risks in addition to those risks associated with investing in the real estate industry in general. An equity REIT may be affected by changes in the value of the underlying properties owned by the REIT. A mortgage REIT may be affected by changes in interest rates and the ability of the issuers of its portfolio mortgages to repay their obligations. REITs are dependent upon the skills of their managers and are not diversified. REITs are generally dependent upon maintaining cash flows to repay borrowings and to make distributions to shareholders and are subject to the risk of default by lessees or borrowers. REITs whose underlying assets are concentrated in properties used by a particular industry, such as health care, are also subject to risks associated with such industry. REITs (especially mortgage REITs) are also subject to interest rate risks. When interest rates decline, the value of a REIT's investment in fixed rate obligations can be expected to rise. Conversely, when interest rates rise, the value of a REIT's investment in fixed rate obligations can be expected to decline. If the REIT invests in adjustable rate mortgage loans the interest rates on which are reset periodically, yields on a REIT's investments in such loans will gradually align themselves to reflect changes in market interest rates. This causes the value of such investments to fluctuate less dramatically in response to interest rate fluctuations than would investments in fixed rate obligations. REITs may have limited financial resources, may utilize significant amounts of leverage, may trade less frequently and in a limited volume and may be subject to more abrupt or erratic price movements than larger company securities. Historically, REITs have been more volatile in price than the larger capitalization stocks included in Standard & Poor's 500 Stock Index. |  |  |  |  |  |  |  |  |  |  |  |
Risks Associated with Options (All Funds Except CPZ) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Risks Associated with Options (all Funds except CPZ). There are several risks associated with transactions in options. For example, there are significant differences between the securities markets and options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well- conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The Fund's ability to utilize options successfully will depend on Calamos' ability to predict pertinent market movements, which cannot be assured. The Fund may sell options on individual securities and securities indices. All call options sold by the Fund must be "covered." Even though the Fund will receive the option premium to help protect it against loss, a call option sold by the Fund exposes the Fund during the term of the option to possible loss of opportunity to realize appreciation in the market price of the underlying security or instrument and may require the Fund to hold a security or instrument that it might otherwise have sold. In addition, a loss on a call option sold may be greater than the premium received. The Fund may purchase and sell put options on individual securities and securities indices. In selling put options, there is a risk that the Fund may be required to buy the underlying security at a disadvantageous price above the market price. |  |  |  |  |  |  |  |  |  |  |  |
Risks Associated With Options Cpz [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Risks Associated with Options (CPZ). The Fund may use options, including on the Fund's convertible securities or during the creation of synthetic convertible instruments. There are several risks associated with transactions in options. For example, there are significant differences between the securities markets and options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. A decision as to whether, when and how to use options involves the exercise of skill and judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events. The Fund's ability to utilize options successfully will depend on Calamos' ability to predict pertinent market movements, which cannot be assured. The Fund intends to seek to generate income from option premiums by writing (selling) options. The Fund may write (sell) call options (i) on a portion of the equity securities (including securities that are convertible into equity securities) in the Fund's portfolio, (ii) on a portion of the equity securities the Fund has a right to receive upon conversion of a convertible security that it owns at the time it writes the call, and (iii) on broad-based securities indexes (such as the S&P 500 or MSCI EAFE) or certain ETFs that trade like common stocks but seek to replicate such market indexes. All call options sold by the Fund must be "covered", other than those sold in the Long/Short Component. For example, a call option written by the Fund will require the Fund to hold the securities subject to the call (or securities convertible into the needed securities without additional consideration) or to segregate cash or liquid assets sufficient to purchase and deliver the securities if the call is exercised. Even though the Fund will receive the option premium to help protect it against loss, a call option sold by the Fund exposes the Fund during the term of the option to possible loss of opportunity to realize appreciation in the market price of the underlying security or instrument and may require the Fund to hold a security or instrument that it might otherwise have sold. The Fund may purchase and sell put options on individual securities and securities indices. In selling put options, there is a risk that the Fund may be required to buy the underlying security at a disadvantageous price above the market price. A put option written by the Fund requires the Fund to segregate cash or liquid assets equal to the exercise price minus any margin the Fund is required to post. |  |  |  |  |  |  |  |  |  |  |  |
Rule 144 Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Rule 144A Securities Risk. The Fund may invest in securities that are issued and sold through transactions under Rule 144A of the Securities Act of 1933. Under the supervision and oversight of the Board of Trustees, Calamos will determine whether Rule 144A Securities are illiquid. If qualified institutional buyers are unwilling to purchase these Rule 144A Securities, the percentage of the Fund's assets invested in illiquid securities would increase. Typically, the Fund purchases Rule 144A Securities only if the Fund's adviser has determined them to be liquid. If any Rule 144A Security held by the Fund should become illiquid, the value of the security may be reduced and a sale of the security may be more difficult. |  |  |  |  |  |  |  |  |  |  |  |
Sector Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Sector Risk. To the extent the Fund invests a significant portion of its assets in a particular sector, a greater portion of the Fund's performance may be affected by the general business and economic conditions affecting that sector. Each sector may share economic risk with the broader market, however there may be economic risks specific to each sector. As a result, returns from those sectors may trail returns from the overall stock market and it is possible that the Fund may underperform the broader market, or experience greater volatility. |  |  |  |  |  |  |  |  |  |  |  |
Synthetic Convertible Instruments Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Synthetic Convertible Instruments Risk. The value of a synthetic convertible instrument may respond differently to market fluctuations than a convertible instrument because a synthetic convertible instrument is composed of two or more separate securities, each with its own market value. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value. Synthetic convertible instruments created by other parties have the same attributes of a convertible security; however, the issuer of the synthetic convertible instrument assumes the credit risk associated with the investment, rather than the issuer of the underlying equity security into which the instrument is convertible. Investing in synthetic convertible instruments also involves the risk that the Fund does not achieve the investment exposure desired by Calamos. The Fund remains subject to the credit risk associated with the counterparty creating the synthetic convertible instrument. |  |  |  |  |  |  |  |  |  |  |  |
Tax Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Tax Risk. The Fund may invest in certain securities, such as certain convertible securities and high yield securities, for which the federal income tax treatment may not be clear or may be subject to re-characterization by the Internal Revenue Service ("IRS"). It could be more difficult for the Fund to comply with certain federal income tax requirements applicable to regulated investment companies if the tax characterization of the Fund's investments is not clear or if the tax treatment of the income from such investments was successfully challenged by the IRS. In addition, the tax treatment of the Fund may be affected by future interpretations of the Internal Revenue Code of 1986, as amended and changes in the tax laws and regulations, all of which may apply with retroactive effect. |  |  |  |  |  |  |  |  |  |  |  |
Us Government Security Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | US Government Security Risk. Some securities issued by US Government agencies or government sponsored enterprises are not backed by the full faith and credit of the US and may only be supported by the right of the agency or enterprise to borrow from the US Treasury. There can be no assurance that the US Government will always provide financial support to those agencies or enterprises. |  |  |  |  |  |  |  |  |  |  |  |
Volatility Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Volatility Risk. Risk may arise in connection with the use of derivative instruments from volatility of interest rates and the prices of reference instruments. |  |  |  |  |  |  |  |  |  |  |  |
Currency Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Currency Risk. To the extent that the Fund invests in securities or other instruments denominated in or indexed to foreign currencies, changes in currency exchange rates bring an added dimension of risk. Currency fluctuations could negatively impact investment gains or add to investment losses. Although the Fund may attempt to hedge against currency risk, the hedging instruments may not always perform as the Fund expects and could produce losses. Suitable hedging instruments may not be available for currencies of emerging market countries. The Fund's investment adviser may determine not to hedge currency risks, even if suitable instruments appear to be available. |  |  |  |  |  |  |  |  |  |  |  |
Cybersecurity Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Cybersecurity Risk. Investment companies, such as the Fund, and their service providers are exposed to operational and information security risks resulting from cyberattacks, which may result in financial losses to a fund and its shareholders. Cyber-attacks include, among other behaviors, stealing or corrupting data maintained online or digitally, denial of service attacks on websites, "ransomware" that renders systems inoperable until ransom is paid, the unauthorized release of confidential information, or various other forms of cybersecurity breaches. Cyber-attacks affecting the Fund or the Adviser, custodian, transfer agent, distributor, administrator, intermediaries, trading counterparties, and other third-party service providers may adversely impact the Fund or the companies in which the Fund invests, causing the Fund's investments to lose value or to prevent a shareholder redemption or purchase from clearing in a timely manner. |  |  |  |  |  |  |  |  |  |  |  |
Inflation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Inflation Risk. Inflation is the reduction in the purchasing power of money resulting from an increase in the price of goods and services. Inflation risk is the risk that the inflation adjusted or "real" value of an investment in preferred stock or debt securities or the income from that investment will be worth less in the future. As inflation occurs, the real value of the preferred stock or debt securities and the dividend payable to holders of preferred stock or interest payable to holders of debt securities declines. |  |  |  |  |  |  |  |  |  |  |  |
Leverage Risk For All Funds Except Cpz [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Leverage Risk (for all Funds except CPZ). The Fund has issued indebtedness and preferred shares and may borrow money or issue debt securities as permitted by the 1940 Act. As of October 31, 2023, the Fund has leverage in the form of borrowings under the SSB Agreement and outstanding MRP Shares. Leverage is the potential for the Fund to participate in gains and losses on an amount that exceeds the Fund's investment. The borrowing of money or issuance of debt securities and preferred shares represents the leveraging of the Fund's common shares. As a non-fundamental policy, the Fund may not issue preferred shares or borrow money and/or issue debt securities with an aggregate liquidation preference and aggregate principal amount exceeding 38% of the Fund's managed assets as measured at the time of borrowing or issuance of the new securities. However, the Board of Trustees reserves the right to issue preferred shares or debt securities or borrow to the extent permitted by the 1940 Act and the Fund's policies. Leverage creates risks which may adversely affect the return for the holders of common shares, including: • the likelihood of greater volatility in the NAV and market price of the Fund's common shares; • fluctuations in the dividend rates on any preferred shares borne by the Fund or in interest rates on borrowings and short-term debt; • increased operating costs, which are effectively borne by common shareholders, may reduce the Fund's total return; and • the potential for a decline in the value of an investment acquired with borrowed funds, while the Fund's obligations under such borrowing or preferred shares remain fixed. In addition, the rights of lenders and the holders of preferred shares and debt securities issued by the Fund will be senior to the rights of the holders of common shares with respect to the payment of dividends or to the payment of assets upon liquidation. Holders of preferred shares have voting rights in addition to and separate from the voting rights of common shareholders. The holders of preferred shares or debt, if any, on the one hand, and the holders of the common shares, on the other, may have interests that conflict in certain situations. Leverage is a speculative technique that could adversely affect the returns to common shareholders. Leverage can cause the Fund to lose money and can magnify the effect of any losses. To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the Fund's return will be greater than if leverage had not been used. Conversely, if the income or capital appreciation from the securities purchased with such funds is not sufficient to cover the cost of leverage or if the Fund incurs capital losses, the return of the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced or potentially eliminated. The Fund will pay, and common shareholders will effectively bear, any costs and expenses relating to any borrowings and to the issuance and ongoing maintenance of preferred shares or debt securities. Such costs and expenses include the higher management fee resulting from the use of any such leverage, offering and/or issuance costs, and interest and/or dividend expense and ongoing maintenance. These conditions may, directly or indirectly, result in higher leverage costs to common shareholders. Certain types of borrowings may result in the Fund being subject to covenants in credit agreements, including those relating to asset coverage, borrowing base and portfolio composition requirements and additional covenants that may affect the Fund's ability to pay dividends and distributions on common shares in certain instances. The Fund may also be required to pledge its assets to the lenders in connection with certain types of borrowings. The Fund may be subject to certain restrictions on investments imposed by guidelines of and covenants with rating agencies which may issue ratings for the preferred shares or short-term debt instruments issued by the Fund. These guidelines and covenants may impose asset coverage or portfolio composition requirements that are more stringent than those imposed by the 1940 Act. The Board of Trustees reserves the right to change the amount and type of leverage that the Fund uses, and reserves the right to implement changes to the Fund's borrowings that it believes are in the long-term interests of the Fund and its shareholders, even if such changes impose a higher interest rate or other costs or impacts over the intermediate, or short-term time period. There is no guarantee that the Fund will maintain leverage at the current rate, and the Board of Trustees reserves the right to raise, decrease, or eliminate the Fund's leverage exposure. If the Fund's ability to make dividends and distributions on its common shares is limited, such limitation could, under certain circumstances, impair the ability of the Fund to maintain its qualification for taxation as a regulated investment company or to reduce or eliminate tax at the Fund level, which would have adverse tax consequences for common shareholders. To the extent that the Fund is required, in connection with maintaining 1940 Act asset coverage requirements or otherwise, or elects to redeem any preferred shares or debt securities or prepay any borrowings, the Fund may need to liquidate investments to fund such redemptions or prepayments. Liquidation at times of adverse economic conditions may result in capital loss and reduce returns to common shareholders. Because Calamos' investment management fee is a percentage of the Fund's managed assets, Calamos' fee will be higher if the Fund is leveraged and Calamos will have an incentive to be more aggressive and leverage the Fund. Consequently, the Fund and Calamos may have differing interests in determining whether to leverage the Fund's assets. Any additional use of leverage by the Fund effected through new, additional or increased credit facilities or the issuance of preferred shares would require approval by the Board. In considering whether to approve the use of additional leverage, the Board would be presented with all relevant information necessary to make a determination whether or not additional leverage through those means would be in the best interests of the Fund, including information regarding any potential conflicts of interest. |  |  |  |  |  |  |  |  |  |  |  |
Leverage Risk For C P Z [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Leverage Risk (CPZ). The Fund anticipates that it will issue indebtedness and may issue preferred shares or borrow money or issue debt securities as permitted by the 1940 Act. As of October 31, 2023, the Fund has leverage in the form of borrowings under the SSB Agreement. Leverage is the potential for the Fund to participate in gains and losses on an amount that exceeds the Fund's investment. The borrowing of money or issuance of debt securities and preferred shares represents the leveraging of the Fund's common shares. As a non-fundamental policy, the Fund may not issue preferred shares or borrow money and issue debt securities with an aggregate liquidation preference and aggregate principal amount exceeding 38% of the Fund's total assets. However, the Board reserves the right to issue preferred shares or borrow to the extent permitted by the 1940 Act and the Fund's policies. Investments of short sale proceeds and economic leverage through derivatives are not counted as borrowings. Leverage creates risks which may adversely affect the return for the holders of common shares, including: • the likelihood of greater volatility in the NAV and market price of the Fund's common shares; • fluctuations in the interest rates on borrowings and short-term debt; • increased operating costs, which are effectively borne by common shareholders, may reduce the Fund's total return; and • the potential for a decline in the value of an investment acquired with borrowed funds, while the Fund's obligations under such borrowing remain fixed. The Fund's use of leverage is premised upon the expectation that the Fund's preferred share dividends or borrowing cost will be lower than the return the Fund achieves on its investments with the proceeds of the issuance of senior securities or borrowing. Such difference in return may result from the Fund's higher credit rating or the short-term nature of its borrowing compared to the lower credit quality, long-term nature of its investments. Because Calamos seeks to invest the Fund's managed assets (including the assets obtained from leverage) in a portfolio of potentially higher yielding investments or portfolio investments with the potential for capital appreciation, the holders of common shares will be the beneficiaries of the incremental return but will bear the risk of loss on investments made with the leverage proceeds. Should the differential between the Fund's return on investments made with the proceeds of leverage and the cost of the leverage narrow, the incremental return "pick up" will be reduced or the Fund may incur losses. Furthermore, if long-term interest rates rise without a corresponding increase in the yield on the Fund's portfolio investments or the Fund otherwise incurs losses on its investments, the Fund's NAV attributable to its common shares will reflect the decline in the value of portfolio holdings resulting therefrom. Leverage is a speculative technique that could adversely affect the returns to holders of common shares. Leverage can cause the Fund to lose money and can magnify the effect of any losses. To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the Fund's return will be greater than if leverage had not been used. Conversely, if the income or capital appreciation from the securities purchased with such funds is not sufficient to cover the cost of leverage or if the Fund incurs capital losses, the return of the Fund will be less than if leverage had not been used, and therefore the amount available for distribution to common shareholders as dividends and other distributions will be reduced or potentially eliminated. The Fund will pay, and common shareholders will effectively bear, any costs and expenses relating to any borrowings and to the issuance and ongoing maintenance of debt. Such costs and expenses include the higher management fee resulting from the use of any such leverage, offering and/or issuance costs, and interest expense and ongoing maintenance. These conditions may, directly or indirectly, result in higher leverage costs to common shareholders. Certain types of borrowings may result in the Fund being subject to covenants in credit agreements, including those relating to asset coverage, borrowing base and portfolio composition requirements and additional covenants that may affect the Fund's ability to pay dividends and distributions on common shares in certain instances. The Fund may also be required to pledge its assets to the lenders in connection with certain types of borrowings. The Fund may be subject to certain restrictions on investments imposed by guidelines of rating agencies which may issue ratings for the short-term debt instruments issued by the Fund. These guidelines may impose asset coverage or portfolio composition requirements that are more stringent than those imposed by the 1940 Act. If the Fund's ability to make dividends and distributions on its common shares is limited, such limitation could, under certain circumstances, impair the ability of the Fund to maintain its qualification for taxation as a regulated investment company or to reduce or eliminate tax at the Fund level, which would have adverse tax consequences for common shareholders. To the extent that the Fund is required, in connection with maintaining 1940 Act asset coverage requirements or otherwise, or elects to redeem any senior securities or prepay any borrowings, the Fund may need to liquidate investments to fund such redemptions or prepayments. Liquidation at times of adverse economic conditions may result in capital loss and reduce returns to common shareholders. Because Calamos' investment management fee is a percentage of the Fund's managed assets, Calamos' fee will be higher if the Fund is leveraged and Calamos will have an incentive to be more aggressive and leverage the Fund. Consequently, the Fund and Calamos may have differing interests in determining whether to leverage the Fund's assets. Any additional use of leverage by the Fund would require approval by the Board. In considering whether to approve the use of additional leverage, the Board would be presented with all relevant information necessary to make a determination whether or not additional leverage would be in the best interests of the Fund, including information regarding any potential conflicts of interest. |  |  |  |  |  |  |  |  |  |  |  |
Loan Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Loan Risk. The Fund may invest in loans which may not be (i) rated at the time of investment, (ii) registered with the SEC or (iii) listed on a securities exchange. There may not be as much public information available regarding these loans as is available for other Fund investments, such as exchange-listed securities. As well, there may not be an active trading market for some loans, meaning they may be illiquid and more difficult to value than other more liquid securities. Settlement periods for loans are longer than for exchange traded securities, typically ranging between 1 and 3 weeks, and in some cases much longer. There is no central clearinghouse for loan trades, and the loan market has not established enforceable settlement standards or remedies for failure to settle. Because the interest rates of floating-rate loans in which the Fund may invest may reset frequently, if market interest rates fall, the loans' interest rates will be reset to lower levels, potentially reducing the Fund's income. Because the adviser may wish to invest in the publicly traded securities of an obligor, the Fund may not have access to material non-public information regarding the obligor to which other investors have access |  |  |  |  |  |  |  |  |  |  |  |
Market Discount Risk 1 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Market Discount Risk. The Fund's common shares have traded both at a premium and at a discount relative to NAV. Common shares of closed-end investment companies frequently trade at a discount from NAV, but in some cases trade above NAV. The risk of the Fund's common shares trading at a discount is a risk separate from the risk of a decline in the Fund's NAV as a result of investment activities. The Fund's NAV may be reduced immediately following an offering by the offering costs for common shares or other securities, which will be borne entirely by all common shareholders. The Fund's common shares are designed primarily for long-term investors, and you should not purchase common shares if you intend to sell them shortly after purchase. Whether shareholders will realize a gain or loss upon the sale of the Fund's common shares depends upon whether the market value of the shares at the time of sale is above or below the price the shareholder paid, taking into account transaction costs for the shares, and is not directly dependent upon the Fund's NAV. Because the market value of the Fund's common shares will be determined by factors such as the relative demand for and supply of the shares in the market, general market conditions and other factors beyond the control of the Fund, the Fund cannot predict whether its common shares will trade at, below or above the Fund's NAV, or below or above the public offering price for the common shares. |  |  |  |  |  |  |  |  |  |  |  |
Market Disruption Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Market Disruption Risk. Certain events have a disruptive effect on the securities markets, such as terrorist attacks, war and other geopolitical events, earthquakes, storms and other disasters. The Fund cannot predict the effects of similar events in the future on the US economy or any foreign economy. |  |  |  |  |  |  |  |  |  |  |  |
Market Impact Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Market Impact Risk. The sale of the Fund's common shares (or the perception that such sales may occur) may have an adverse effect on prices in the secondary market for the Fund's common shares. An increase in the number of common shares available may put downward pressure on the market price for the Fund's common shares. These sales also might make it more difficult for the Fund to sell additional equity securities in the future at a time and price the Fund deems appropriate. Ratings and Asset Coverage Risk. To the extent that senior securities are rated, a rating does not eliminate or necessarily mitigate the risks of investing in the Fund's senior securities, and a rating may not fully or accurately reflect all of the credit and market risks associated with that senior security. A rating agency could downgrade the rating of the Fund's shares of preferred stock or debt securities, which may make such securities less liquid in the secondary market, though potentially with higher resulting interest rates. If a rating agency downgrades the rating assigned to a senior security, the Fund may alter its portfolio or redeem the senior security. The Fund may voluntarily redeem senior securities under certain circumstances |  |  |  |  |  |  |  |  |  |  |  |
Reduction Of Leverage Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Reduction of Leverage Risk. A Fund may take action to reduce the amount of leverage it employs. Reduction of the leverage employed by the Fund, including by redemption of preferred shares (if applicable), will in turn reduce the amount of assets available for investment in portfolio securities. This reduction in leverage may negatively impact the Fund's financial performance, including the Fund's ability to sustain current levels of distributions on common shares. The Board reserves the right to change the amount and type of leverage that the Fund uses, and reserves the right to implement changes to the Fund's borrowings that it believes are in the best long-term interests of the Fund and its shareholders, even if such changes impose a higher interest rate or other costs or impacts over the intermediate, or short-term time period. There is no guarantee that the Fund will maintain leverage at the current rate, and the Board reserves the right to raise, decrease, or eliminate the Fund's leverage exposure. |  |  |  |  |  |  |  |  |  |  |  |
Secondary Market Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Secondary Market Risk. The market value of exchange-listed preferred shares that the Fund may issue will be determined by factors such as the relative demand for and supply of the preferred shares in the market, general market conditions and other factors beyond the control of the Fund. It may be difficult to predict the trading patterns of preferred shares, including the effective costs of trading. There is a risk that the market for preferred shares may be thinly traded and relatively illiquid compared to the market for other types of securities. |  |  |  |  |  |  |  |  |  |  |  |
Senior Leverage Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk [Text Block] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Senior Leverage Risk. Preferred shares will be junior in liquidation and with respect to distribution rights to debt securities and any other borrowings. Senior securities representing indebtedness may constitute a substantial lien and burden on preferred shares by reason of their prior claim against the Fund's income and against the Fund's net assets in liquidation. The Fund may not be permitted to declare dividends or other distributions with respect to any series of preferred shares unless at such time the Fund meets applicable asset coverage requirements and the payment of principal or interest is not in default with respect to any borrowings. |  |  |  |  |  |  |  |  |  |  |  |
Loan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  | $ 314,400,000 |  |  |  |  |  |  |  | $ 339,400,000 |  |  |  |  |  |  | $ 399,400,000 |  |  |  |  |  |  |  | $ 314,400,000 |  | $ 339,400,000 | $ 399,400,000 |  | $ 288,400,000 | $ 277,400,000 | $ 288,000,000 | $ 275,000,000 | $ 306,000,000 | $ 353,000,000 | $ 360,000,000 |
Senior Securities Coverage per Unit | [12] | $ 3,564 |  |  |  |  |  |  |  | $ 3,630 |  |  |  |  |  |  | $ 4,116 |  |  |  |  |  |  |  | $ 3,564 |  | $ 3,630 | $ 4,116 |  | $ 4,431 | $ 4,080 | $ 3,921 | $ 4,265 | $ 3,454 | $ 3,316 | $ 3,588 |
Mandatory Redeemable Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  | $ 133,000,000 |  |  |  |  |  |  |  | $ 133,000,000 |  |  |  |  |  |  | $ 133,000,000 |  |  |  |  |  |  |  | $ 133,000,000 |  | $ 133,000,000 | $ 133,000,000 |  | $ 100,000,000 | $ 100,000,000 | $ 100,000,000 | $ 100,000,000 |  |  |  |
Senior Securities Coverage per Unit | [13] | $ 211 |  |  |  |  |  |  |  | $ 232 |  |  |  |  |  |  | $ 309 |  |  |  |  |  |  |  | $ 211 |  | $ 232 | $ 309 |  | $ 319 | $ 283 | $ 282 | $ 293 |  |  |  |
Preferred Stock Liquidating Preference | [14] | $ 25 |  |  |  |  |  |  |  | $ 25 |  |  |  |  |  |  | $ 25 |  |  |  |  |  |  |  | 25 |  | 25 | 25 |  | 25 | 25 | 25 | 25 |  |  |  |
Senior Securities Average Market Value per Unit | [15] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 25 |  | $ 25 | $ 25 |  | $ 25 | $ 25 | $ 25 | $ 25 |  |  |  |
Common Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital Stock, Long-Term Debt, and Other Securities [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding Security, Held [Shares] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 74,818,167 |  |  |  |  |  |  |  |  |  |  |  |
[1] | If the securities to which this prospectus relates are sold to or through underwriters, the prospectus supplement will set forth any applicable sales load and the estimated offering expenses borne by us.
[2] | Shareholders will pay a $15.00 transaction fee plus a $0.02 per share brokerage charge if they direct the Plan Agent (as defined below) to sell common shares held in a Plan account. In addition, each participant will pay a pro rata share of brokerage commissions incurred with respect to the Plan Agent's open-market purchases in connection with the reinvestment of dividends or distributions. If a participant elects to have the Plan Agent sell part or all of his or her common shares and remit the proceeds, such participant will be charged his or her pro rata share of brokerage commissions on the shares sold. See "Dividends and Distributions on Common Shares; Automatic Dividend Reinvestment Plan".
[3] | The Fund pays Calamos an annual management fee, payable monthly in arrears, for its investment management services in an amount equal to 0.80% of the Fund's average weekly managed assets. In accordance with the requirements of the Commission, the table above shows the Fund's management fee as a percentage of average net assets attributable to common shareholders. By showing the management fee as a percentage of net assets, the management fee is not expressed as a percentage of all of the assets the Fund intends to invest. For purposes of the table, the management fee has been converted to 1.29% of the Fund's average weekly net assets as of October 31, 2023 by dividing the total dollar amount of the management fee by the Fund's average weekly net assets (managed assets less outstanding leverage).
[4] | Reflects interest expense paid on $166 million in average borrowings under the SSB Agreement, plus $52 million in additional average structural leverage related to certain securities lending programs, as described under "Leverage".
[5] | Reflects estimated dividend expense on $92 million aggregate liquidation preference of mandatory redeemable preferred shares outstanding. See "Leverage".
[6] | "Other Expenses" are based on estimated amounts for the Fund's current fiscal year.
[7] | The example does not include sales load or estimated offering costs, which would cause the expenses shown in the example to increase. In connection with an offering of common shares, the applicable prospectus supplement will set forth an example including sales load and estimated offering costs.
[8] | Includes interest expense on the borrowings under the SSB Agreement, accrued at interest rates in effect on October 31, 2023 of 5.84%, and dividend expense on the MRP Shares.
[9] | Based on high and low closing market price per share during the respective quarter and does not reflect commissions.
[10] | Premium and discount information is shown for the days when the Fund experienced its high and low closing market prices, respectively, per share during the respective quarter.
[11] | Based on the NAV calculated on the close of business on the last business day of each calendar quarter.
[12] | Calculated by subtracting the Fund's total liabilities (not including notes payable) from the Fund's total assets and dividing this by the amount of notes payable outstanding, and by multiplying the result by 1,000.
[13] | Calculated by subtracting the Fund's total liabilities (not including MRPS) from the Fund's total assets and dividing this by the number of MRPS outstanding, and by multiplying the result by 25.
[14] | "Liquidating Preference per Preferred Share" means the amount to which a holder of preferred shares would be entitled upon the liquidation of the Fund in preference to common shareholders, expressed as a dollar amount per preferred share.
[15] | The MRPS are not listed on any exchange or automated quotation system. The MRPS are considered debt of the issuer; and the liquidation preference approximates fair value.

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