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[Axis] Industry Sector [Axis] Federal Housing Administration (“FHA”) loans Federal Housing Administration (“FHA”) Loans [Member] Federal Housing Administration (“FHA”) Loans Eclipse Business Capital, LLC Eclipse Business Capital, LLC [Member] Eclipse Business Capital, LLC Existing Portfolio Existing Portfolio [Member] Existing Portfolio Utilities: Electric Utilities: Electric [Member] Utilities: Electric PEO PEO [Member] Sierra Credit Support Agreement Covered Credit Losses Minimum New Sierra Credit Support Agreement Covered Credit Losses Minimum [Member] New Sierra Credit Support Agreement Covered Credit Losses Minimum Citibank N.A. Subscription Facility Citibank N.A. Subscription Facility [Member] Citibank N.A. 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Subsequent Event Type [Domain] Total Distributable Earnings (Loss) Retained Earnings [Member] Combined weighted average interest rate Long-Term Debt, Weighted Average Interest Rate, over Time Investment Company [Abstract] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Total increase (decrease) from investment operations (in dollars per share) Investment Company, Investment Income (Loss) from Operations, Per Share Debt securities, structured product position Debt Securities, Structured Product Position [Member] Debt Securities, Structured Product Position Schedule of Fair Value Measurement Inputs and Valuation Techniques Schedule of Significant Unobservable Inputs used in Valuation Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Common stock, shares outstanding (in shares) Beginning balance (in shares) Ending balance (in shares) Shares outstanding at end of period (in shares) Common Stock, Shares, Outstanding Award 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