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BORROWINGS - Notes Payable (Narrative) (Details) - USD ($) $ in Thousands | 1 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2024 | May 31, 2023 | Aug. 31, 2021 | Mar. 31, 2021 | Jun. 30, 2025 | Mar. 31, 2025 | Jun. 30, 2024
Debt Instrument [Line Items] |  |  |  |  |  |  |
Total borrowings, at cost |  |  |  |  | $ 525,738 |  | $ 400,938
Notes Payable |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Total borrowings, at cost |  |  |  |  | $ 463,738 | $ 463,738 |
5.00% Notes due 2026 | Notes Payable |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate |  |  |  | 5.00% | 5.00% | 5.00% |
Total borrowings, at cost |  |  |  | $ 127,900 | $ 127,938 | $ 127,938 |
Proceeds from issuance of long-term debt |  |  |  | 123,800 |  |  |
Borrowings outstanding at cost |  |  |  | $ 4,100 |  |  |
Notes payable, fair value disclosure |  |  |  |  | $ 127,500 | $ 127,500 |
4.875% Notes due 2028 | Notes Payable |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate |  |  | 4.875% |  | 4.875% | 4.875% |
Total borrowings, at cost |  |  | $ 134,600 |  | $ 134,550 | $ 134,550 |
Proceeds from issuance of long-term debt |  |  | 131,300 |  |  |  |
Borrowings outstanding at cost |  |  | $ 3,300 |  |  |  |
Notes payable, fair value disclosure |  |  |  |  | $ 123,400 | $ 125,000 |
8.00% 2028 Notes | Notes Payable |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate |  | 8.00% |  |  | 8.00% | 8.00% |
Total borrowings, at cost |  | $ 74,800 |  |  | $ 74,750 | $ 74,750 |
Proceeds from issuance of long-term debt |  | 72,300 |  |  |  |  |
Borrowings outstanding at cost |  | $ 2,500 |  |  |  |  |
Notes payable, fair value disclosure |  |  |  |  | $ 76,500 | $ 77,500 |
7.875% 2030 Notes | Notes Payable |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate | 7.875% |  |  |  | 7.875% | 7.875% |
Total borrowings, at cost | $ 126,500 |  |  |  | $ 126,500 | $ 126,500 |
Proceeds from issuance of long-term debt | 122,400 |  |  |  |  |  |
Borrowings outstanding at cost | $ 4,100 |  |  |  |  |  |
Notes payable, fair value disclosure |  |  |  |  | $ 127,500 | $ 128,500 |

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