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INVESTMENTS - Fair Value Measurement Inputs and Valuation Techniques (Details) $ in Thousands | Sep. 30, 2023 USD ($) | Mar. 31, 2023 USD ($)
--- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | $ 915,636 | $ 753,543 | [1]
Investments at fair value | 915,636 | 753,543 |
Secured First Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 508,504 | 437,517 |
Secured Second Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 102,747 | 75,734 |
Preferred Equity |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 267,596 | 222,585 |
Common Equity/ Equivalents |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 36,789 | 17,707 |
Significant Unobservable Inputs (Level 3) |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 915,614 | 753,516 |
Investments at fair value | 915,614 | 753,516 |
Significant Unobservable Inputs (Level 3) | Secured First Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 508,504 | 437,517 |
Significant Unobservable Inputs (Level 3) | Secured Second Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 102,747 | 75,734 |
Significant Unobservable Inputs (Level 3) | Preferred Equity |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 267,596 | 222,585 |
Significant Unobservable Inputs (Level 3) | Common Equity/ Equivalents |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 36,767 | 17,680 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Secured First Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 494,812 | 432,126 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Secured Second Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 77,997 | 62,750 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Preferred Equity |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 267,596 | 222,585 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Common Equity/ Equivalents |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | $ 36,767 | $ 17,680 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Secured First Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 3.7 | 4.4 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Secured First Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 10.8 | 7.7 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Secured First Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 6.8 | 6.4 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Secured Second Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 5.3 | 5.4 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Secured Second Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 10.3 | 6.6 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Secured Second Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 6.6 | 6.2 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Preferred Equity | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 3.7 | 4.4 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Preferred Equity | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 10.8 | 7.7 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Preferred Equity | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 6.4 | 5.9 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Common Equity/ Equivalents | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 4.8 | 4.7 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Common Equity/ Equivalents | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 10.3 | 7.2 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA multiple | Common Equity/ Equivalents | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 5.8 | 6.4 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Secured First Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | $ 1,278 | $ 4,251 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Secured First Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 21,338 | 19,083 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Secured First Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 10,590 | 10,764 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Secured Second Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 6,134 | 4,112 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Secured Second Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 9,684 | 6,379 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Secured Second Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 7,110 | 5,501 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Preferred Equity | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 3,176 | 4,251 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Preferred Equity | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 21,338 | 19,083 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Preferred Equity | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 9,278 | 9,486 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Common Equity/ Equivalents | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 1,278 | 1,105 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Common Equity/ Equivalents | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 59,739 | 30,833 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | EBITDA | Common Equity/ Equivalents | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | $ 22,467 | $ 6,273 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue multiple | Secured First Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.3 | 0.3 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue multiple | Secured First Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.6 | 0.6 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue multiple | Secured First Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.3 | 0.3 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue multiple | Preferred Equity | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.3 | 0.3 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue multiple | Preferred Equity | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.6 | 0.6 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue multiple | Preferred Equity | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.4 | 0.4 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue | Secured First Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | $ 15,557 | $ 15,483 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue | Secured First Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 98,181 | 109,615 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue | Secured First Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 85,316 | 94,957 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue | Preferred Equity | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 15,557 | 15,483 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue | Preferred Equity | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 98,181 | 109,615 |
Significant Unobservable Inputs (Level 3) | Total Enterprise Value | Revenue | Preferred Equity | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 62,749 | 69,247 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Secured First Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | 13,692 | 5,391 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Secured Second Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair Value | $ 24,750 | $ 12,984 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Discount Rate | Secured First Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.249 | 0.194 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Discount Rate | Secured First Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.249 | 0.199 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Discount Rate | Secured First Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.249 | 0.197 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Discount Rate | Secured Second Lien Debt | Minimum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.141 | 0.140 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Discount Rate | Secured Second Lien Debt | Maximum |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.141 | 0.140 |
Significant Unobservable Inputs (Level 3) | Yield Analysis | Discount Rate | Secured Second Lien Debt | Weighted Average |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Fair value, measurement input | 0.141 | 0.140 |
Significant Other Observable Inputs (Level 2) |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | $ 22 | $ 27 |
Significant Other Observable Inputs (Level 2) | Secured First Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Significant Other Observable Inputs (Level 2) | Secured Second Lien Debt |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Significant Other Observable Inputs (Level 2) | Preferred Equity |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 0 | 0 |
Significant Other Observable Inputs (Level 2) | Common Equity/ Equivalents |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | 22 | 27 |
Significant Other Observable Inputs (Level 2) | Common Equity/ Equivalents | Funko Acquisition Holdings, LLC |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Investments at fair value | $ 22 | $ 27 |
[1] | Cumulative gross unrealized appreciation for federal income tax purposes is $150.4 million; cumulative gross unrealized depreciation for federal income tax purposes is $119.3 million. Cumulative net unrealized appreciation is $31.1 million, based on a tax cost of $722.4 million.

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