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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jul. 18, 2021 | Sep. 30, 2025 USD ($) | Sep. 30, 2024 | Sep. 30, 2025 USD ($) segment investment | Sep. 30, 2024 USD ($) | Mar. 31, 2025 USD ($) investment
Accounting Policies [Abstract] |  |  |  |  |  |
Cash held in money market funds |  | $ 76,600,000 |  | $ 76,600,000 |  | $ 28,100,000
FDIC uninsured amount |  | $ 87,100,000 |  | $ 87,100,000 |  | $ 43,100,000
Number of operating segments | segment |  |  |  | 1 |  |
Number of reportable segments | segment |  |  |  | 1 |  |
Remaining lease term |  | 10 years |  | 10 years |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Number of PIK investments | investment |  |  |  | 4 |  | 5
Non-cash PIK interest income percent |  | 4.90% | 4.90% | 5.40% | 5.50% |
Interest or penalties expense |  |  |  | $ 0 | $ 0 |
Restricted Stock | 2010 Plan |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Right to grant period | 10 years |  |  |  |  |
Investments on Non-accrual Status | Percentage of Total Portfolio at Fair Value | Credit risk |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Percent of total investment portfolio's fair value |  |  |  | 1.00% |  | 1.70%
Investments on Non-accrual Status | Percentage of Total Portfolio at Cost | Credit risk |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |
Percent of total investment portfolio's fair value |  |  |  | 2.60% |  | 3.50%

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