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BORROWINGS - Revolving Line of Credit Narrative (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 30, 2023 | Jun. 30, 2024 | Mar. 31, 2024
Debt Instrument [Line Items] |  |  |
Indebtedness asset coverage on our senior securities |  | 216.30% | 219.00%
Credit Facility | Line of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Unused fee percentage |  | 1.00% | 1.00%
Credit Facility | Revolving Line of Credit | Line of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Commitment amount |  | $ 200,000 | $ 200,000
Debt instrument, variable rate floor |  | 0.35% | 0.35%
Debt instrument, basis spread on variable rate |  | 3.25% | 3.25%
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 |  | 216.30% |
Senior security, indebtedness, asset coverage amount |  | $ 807,500 |
Credit Facility | Revolving Line of Credit | Line of Credit | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Indebtedness asset coverage on our senior securities |  | 150.00% |
Credit Facility | Revolving Line of Credit | Line of Credit | Less than or Equal to 50% of Commitment |  |  |
Debt Instrument [Line Items] |  |  |
Unused fee percentage | 0.50% |  |
Credit Facility | Revolving Line of Credit | 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 | Revolving Line of Credit | Line of Credit | Greater Than 65% Of Commitment |  |  |
Debt Instrument [Line Items] |  |  |
Unused fee percentage | 1.00% |  |
Credit Facility | Revolving Line of Credit | Line of Credit | Secured Overnight Financing Rate (SOFR) |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, variable rate floor | 0.35% |  |
Credit Facility | Revolving Line of Credit | Line of Credit | SOFR, Tranche One |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, basis spread on variable rate | 3.15% |  |
Credit Facility | Revolving Line of Credit | Line of Credit | SOFR, Tranche Two |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, basis spread on variable rate | 3.40% |  |
Credit Facility | Revolving Line of Credit | Line of Credit | SOFR, Thereafter |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, basis spread on variable rate | 3.65% |  |
Credit Facility | Revolving Line of Credit | Line of Credit | SOFR, Thereafter, Adjustment |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, basis spread on variable rate | 0.10% |  |

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