Quarterly report [Sections 13 or 15(d)]

INVESTMENTS - Schedule of Fair Value Measurement Inputs and Valuation Techniques (Details)

v3.26.3
INVESTMENTS - Schedule of Fair Value Measurement Inputs and Valuation Techniques (Details)
$ in Thousands
Sep. 30, 2026
USD ($)
Mar. 31, 2026
USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 1,430,865 $ 1,309,248 [1]
Significant Unobservable Inputs (Level 3)    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 1,425,975 1,304,243
Significant Unobservable Inputs (Level 3) | TEV | Secured First Lien Debt    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 654,079 570,602
Significant Unobservable Inputs (Level 3) | TEV | Secured Second Lien Debt    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 107,333 99,197
Significant Unobservable Inputs (Level 3) | TEV | Preferred Equity    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 484,076 426,949
Significant Unobservable Inputs (Level 3) | TEV | Common Equity/ Equivalents    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 180,487 $ 207,495
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Secured First Lien Debt | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 3.9 3.6
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Secured First Lien Debt | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 9.3 8.7
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Secured First Lien Debt | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 6.6 6.4
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Secured Second Lien Debt | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 4.6 5.0
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Secured Second Lien Debt | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 9.2 10.3
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Secured Second Lien Debt | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 7.8 7.6
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Preferred Equity | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 3.6 3.6
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Preferred Equity | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 9.3 8.7
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Preferred Equity | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 6.0 6.4
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Common Equity/ Equivalents | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 4.6 5.0
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Common Equity/ Equivalents | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 9.2 10.3
Significant Unobservable Inputs (Level 3) | TEV | EBITDA multiple | Common Equity/ Equivalents | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 9.0 9.0
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Secured First Lien Debt | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 206 $ 430
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Secured First Lien Debt | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 25,204 28,973
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Secured First Lien Debt | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 10,990 11,991
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Secured Second Lien Debt | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 4,095 3,000
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Secured Second Lien Debt | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 51,487 44,315
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Secured Second Lien Debt | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 29,796 19,510
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Preferred Equity | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 206 430
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Preferred Equity | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 56,204 28,973
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Preferred Equity | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 20,994 9,870
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Common Equity/ Equivalents | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 2,287 1,210
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Common Equity/ Equivalents | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 51,487 44,315
Significant Unobservable Inputs (Level 3) | TEV | EBITDA | Common Equity/ Equivalents | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 48,317 $ 32,353
Significant Unobservable Inputs (Level 3) | TEV | Revenue multiple | Secured First Lien Debt | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 0.4 0.3
Significant Unobservable Inputs (Level 3) | TEV | 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) | TEV | Revenue multiple | Secured First Lien Debt | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 0.4 0.5
Significant Unobservable Inputs (Level 3) | TEV | Revenue multiple | Preferred Equity | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair value, measurement input 0.4 0.3
Significant Unobservable Inputs (Level 3) | TEV | 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) | TEV | 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) | TEV | Revenue | Secured First Lien Debt | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 18,379 $ 21,768
Significant Unobservable Inputs (Level 3) | TEV | Revenue | Secured First Lien Debt | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 90,572 99,974
Significant Unobservable Inputs (Level 3) | TEV | Revenue | Secured First Lien Debt | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 90,572 62,789
Significant Unobservable Inputs (Level 3) | TEV | Revenue | Preferred Equity | Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 18,379 21,768
Significant Unobservable Inputs (Level 3) | TEV | Revenue | Preferred Equity | Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value 90,572 99,974
Significant Unobservable Inputs (Level 3) | TEV | Revenue | Preferred Equity | Weighted Average    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 90,572 $ 76,364
[1] Cumulative gross unrealized appreciation for federal income tax purposes is $428.5 million; cumulative gross unrealized depreciation for federal income tax purposes is $173.7 million. Cumulative net unrealized appreciation is $254.8 million, based on a tax cost of $1.1 billion.