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v3.25.3

BORROWINGS - Borrowings Outstanding (Details) - USD ($) $ in Thousands | 1 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Aug. 31, 2021 | Sep. 30, 2025 | Mar. 31, 2025
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | $ 1,053,875 | $ 969,875
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (19,117) | (13,810)
Recorded Value |  | 1,034,758 | 956,065
Estimated Fair Value |  | 1,037,998 | 939,710
SBA Debentures |  |  |
Debt Instrument [Line Items] |  |  |
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (4,088) | (4,082)
SBA Debentures | Unsecured Debt |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | 175,000 | 175,000
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (4,088) | (4,082)
Recorded Value |  | 170,912 | 170,918
Estimated Fair Value |  | 168,628 | 166,460
Corporate Credit Facility | Line of Credit | Corporate Credit Facility |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | 0 | 235,000
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | 0 | 0
Recorded Value |  | 0 | 235,000
Estimated Fair Value |  | 0 | 235,000
SPV Credit Facility | Line of Credit | SPV Credit Facility |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | 77,000 | 108,000
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | 0 | 0
Recorded Value |  | 77,000 | 108,000
Estimated Fair Value |  | 77,000 | 108,000
October 2026 Notes |  |  |
Debt Instrument [Line Items] |  |  |
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (769) | (1,154)
October 2026 Notes | Notes |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | 150,000 | 150,000
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (769) | (1,154)
Recorded Value |  | 149,231 | 148,846
Estimated Fair Value |  | $ 150,000 | 130,899
Redemption price, percentage | 100.00% | 100.00% |
August 2028 Notes |  |  |
Debt Instrument [Line Items] |  |  |
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | $ (1,429) | (1,681)
August 2028 Notes | Notes |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | 71,875 | 71,875
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (1,429) | (1,681)
Recorded Value |  | 70,446 | 70,194
Estimated Fair Value |  | 72,860 | 73,571
2029 Convertible Notes |  |  |
Debt Instrument [Line Items] |  |  |
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (6,153) | (6,893)
2029 Convertible Notes | Convertible Debt |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | 230,000 | 230,000
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (6,153) | (6,893)
Recorded Value |  | 223,847 | 223,107
Estimated Fair Value |  | $ 221,944 | 225,780
Redemption price, percentage |  | 100.00% |
September 2030 Notes |  |  |
Debt Instrument [Line Items] |  |  |
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | $ (6,678) | $ 0
September 2030 Notes | Notes |  |  |
Debt Instrument [Line Items] |  |  |
Outstanding Balance |  | 350,000 |
Unamortized Debt Issuance Costs and Debt Discount/Premium |  | (6,678) |
Recorded Value |  | 343,322 |
Estimated Fair Value |  | $ 347,566 |
Redemption price, percentage | 100.00% |  |

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