PROSPECTUS SUPPLEMENT [Member] Dilution Risk [Member] Risks of Investing in Rights [Member] Leverage Risk [Member] Anti-takeover Provisions Risk [Member] Call Risk [Member] Closed-End Fund Risk [Member] Collateralized Loan Obligations Risk [Member] Conflicts of Interest Risk [Member] Convertible Securities Risk [Member] Currency Risk [Member] Depositary Receipts Risk [Member] Derivatives Risk [Member] Distressed Securities Risk [Member] Distributions Risk [Member] Foreign Securities Risk [Member] High Portfolio Turnover Risk [Member] Issuer-Specific Risk [Member] Liquidity Risk [Member] Loan Interests Risk [Member] Lower-Rated Debt Securities Risk [Member] Market Premium/Discount Risk [Member] Market Volatility Risk [Member] Mortgage- and Asset-Backed Securities Risk [Member] Other Investment Company Risk [Member] Operational and Cybersecurity Risk [Member] Prepayment and Extension Risk [Member] Private Placements and Other Restricted Securities Risk [Member] Recent Market Conditions [Member] Regulated Investment Company Status [Member] Repurchase Agreement Risk [Member] Risk Management [Member] Sector Risk [Member] Stockholder Activism Risk [Member] U.S. Government Securities Risk [Member] Valuation Risk [Member] Variable and Floating Rate Instruments Risk [Member] Warrants and Rights Risk [Member] Zero Coupon Securities, Step Coupon Securities, Pay-in-Kind Securities and Discount Obligations [Member] Loans Payable [Member] Mandatory Redeemable Preferred Shares, Series D [Member] Floating Rate Senior Notes [Member] Mandatory Redeemable Preferred Shares, Series C [Member] Mandatory Redeemable Preferred Shares, Series B [Member] Common Stock [Member] Preferred Stock and Loans Outstanding [Member] Preferred Stock (Perpetual Preferred Shares Series A) [Member] Preferred Stock (MRPS Series B) [Member] Preferred Stock (MRPS Series C) [Member] Preferred Stock (MRPS Series D) [Member] Credit Risk [Member]