SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) |
3 Months Ended | 9 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|---|
Apr. 04, 2024 |
Jun. 30, 2025
USD ($)
loan
investment
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Jun. 30, 2024
USD ($)
|
Jun. 30, 2025
USD ($)
loan
investment
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Jun. 30, 2024
USD ($)
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Sep. 30, 2024
USD ($)
loan
investment
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| Schedule of Investments [Line Items] | |||||||||
| Reverse stock split, conversion ratio | 0.5 | ||||||||
| Money market funds | $ 14,900,000 | $ 14,900,000 | $ 2,200,000 | ||||||
| Cost | 777,851,000 | 777,851,000 | 771,011,000 | [1] | |||||
| Fair Value | 751,260,000 | 751,260,000 | 796,260,000 | [1] | |||||
| Total interest income (excluding PIK interest income) | 19,522,000 | $ 21,715,000 | 60,517,000 | $ 65,633,000 | |||||
| PIK interest income | 1,331,000 | 1,484,000 | 2,994,000 | 4,277,000 | |||||
| OID | |||||||||
| Schedule of Investments [Line Items] | |||||||||
| Fair Value | $ 300,000 | $ 300,000 | $ 600,000 | ||||||
| Number of loans | loan | 2 | 2 | 2 | ||||||
| Total interest income (excluding PIK interest income) | $ 200,000 | 100,000 | $ 400,000 | 200,000 | |||||
| PIK | |||||||||
| Schedule of Investments [Line Items] | |||||||||
| Number of investments | investment | 7 | 7 | 8 | ||||||
| Proceeds from interest received | $ 0 | $ 200,000 | $ 7,200,000 | $ 200,000 | |||||
| B+T Group Acquisition, Inc., Edge Adhesives Holdings, Inc,. And WB Xcel Holdings, LLC | |||||||||
| Schedule of Investments [Line Items] | |||||||||
| Cost | $ 28,800,000 | $ 28,800,000 | $ 28,300,000 | ||||||
| Cost percentage | 4.10% | 4.10% | 4.10% | ||||||
| Fair Value | $ 11,500,000 | $ 11,500,000 | $ 12,800,000 | ||||||
| Fair value percentage | 1.70% | 1.70% | 1.90% | ||||||
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- Definition Investment Owned, Percent of Cost Basis No definition available.
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- Definition Investment Owned, Percent of Fair Value No definition available.
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- Definition Number of Investment No definition available.
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- Definition Number of Loan Receivable No definition available.
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- Definition Amount of interest income from investment paid in cash, classified as operating. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of interest income from investment paid in kind, classified as operating. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Cost of the investment. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Fair value of investment in security owned. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. No definition available.
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- Definition Interest received on loans and other debt instruments during the current period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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