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BORROWINGS - Revolving Line of Credit Narrative (Details) - USD ($) $ in Thousands |  |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Oct. 30, 2023 | Apr. 10, 2023 | Mar. 31, 2024 | Mar. 31, 2023 | Feb. 05, 2024 | Feb. 04, 2024 | Oct. 29, 2023
Debt Instrument [Line Items] |  |  |  |  |  |  |
Indebtedness asset coverage on our senior securities |  |  | 219.00% | 244.70% |  |  |
Credit Facility |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, term | 2 years |  |  |  |  |  |
Credit Facility | Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Unused fee percentage |  |  | 1.00% | 1.00% |  |  |
Credit Facility | Line of Credit | Revolving Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity | $ 135,000 |  | $ 200,000 | $ 180,000 | $ 200,000 | $ 135,000 | $ 180,000
Covenant, required minimum net worth of mandatory redeemable term preferred stock |  |  | $ 210,000 |  |  |  |
Covenant, required minimum net worth of mandatory redeemable term preferred stock, plus percent of all equity and subordinated debt raised |  |  | 50.00% |  |  |  |
Covenant, required minimum net worth of mandatory redeemable term preferred stock, minus percent of any equity or subordinated debt redeemed or retired |  |  | 50.00% |  |  |  |
Covenant, required minimum net worth of mandatory redeemable term preferred stock, plus percent of all equity and subordinated debt raised, minus percent of any equity or subordinated debt redeemed or retired |  |  | $ 348,700 |  |  |  |
Indebtedness asset coverage on our senior securities |  |  | 219.00% |  |  |  |
Senior security, indebtedness, asset coverage amount |  |  | $ 822,400 |  |  |  |
Credit Facility | Line of Credit | Revolving Line of Credit | Minimum |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Indebtedness asset coverage on our senior securities |  |  | 150.00% |  |  |  |
Credit Facility | Line of Credit | Revolving Line of Credit | Less than or Equal to 50% of Commitment |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Unused fee percentage |  |  | 0.50% |  |  |  |
Credit Facility | Line of Credit | Revolving Line of Credit | Greater than 50% but Less than or Equal to 65% of Commitment |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Unused fee percentage |  |  | 0.75% |  |  |  |
Credit Facility | Line of Credit | Revolving Line of Credit | Greater Than 65% Of Commitment |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Unused fee percentage |  |  | 1.00% |  |  |  |
Credit Facility | Secured Overnight Financing Rate (SOFR) | Line of Credit | Revolving Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, variable rate floor |  |  | 0.35% |  |  |  |
Debt instrument, basis spread on variable rate |  | 0.11% | 3.25% |  |  |  |
Credit Facility | SOFR, Tranche One | Line of Credit | Revolving Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  |  | 3.15% |  |  |  |
Credit Facility | SOFR, Tranche Two | Line of Credit | Revolving Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  |  | 3.40% |  |  |  |
Credit Facility | SOFR, Thereafter | Line of Credit | Revolving Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  |  | 3.65% |  |  |  |
Credit Facility | SOFR, Thereafter, Adjustment | Line of Credit | Revolving Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  |  | 0.10% |  |  |  |

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