v3.25.4

BORROWINGS - Borrowings Outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Mar. 31, 2025
Debt Instrument [Line Items]
Outstanding Balance	$ 1,089,000	$ 969,875
Unamortized Debt Issuance Costs and Debt Discount/Premium	(16,518)	(13,810)
Recorded Value	1,072,482	956,065
Estimated Fair Value	1,069,479	939,710
SBA Debentures
Debt Instrument [Line Items]
Unamortized Debt Issuance Costs and Debt Discount/Premium	(4,375)	(4,082)
SBA Debentures | Unsecured Debt
Debt Instrument [Line Items]
Outstanding Balance	195,000	175,000
Unamortized Debt Issuance Costs and Debt Discount/Premium	(4,375)	(4,082)
Recorded Value	190,625	170,918
Estimated Fair Value	188,029	166,460
Corporate Credit Facility | Line of Credit | Corporate Credit Facility
Debt Instrument [Line Items]
Outstanding Balance	210,000	235,000
Unamortized Debt Issuance Costs and Debt Discount/Premium	0	0
Recorded Value	210,000	235,000
Estimated Fair Value	210,000	235,000
SPV Credit Facility | Line of Credit | SPV Credit Facility
Debt Instrument [Line Items]
Outstanding Balance	104,000	108,000
Unamortized Debt Issuance Costs and Debt Discount/Premium	0	0
Recorded Value	104,000	108,000
Estimated Fair Value	104,000	108,000
October 2026 Notes
Debt Instrument [Line Items]
Unamortized Debt Issuance Costs and Debt Discount/Premium	0	(1,154)
October 2026 Notes | Notes
Debt Instrument [Line Items]
Outstanding Balance		150,000
Unamortized Debt Issuance Costs and Debt Discount/Premium		(1,154)
Recorded Value		148,846
Estimated Fair Value		130,899
August 2028 Notes
Debt Instrument [Line Items]
Unamortized Debt Issuance Costs and Debt Discount/Premium	0	(1,681)
August 2028 Notes | Notes
Debt Instrument [Line Items]
Outstanding Balance		71,875
Unamortized Debt Issuance Costs and Debt Discount/Premium		(1,681)
Recorded Value		70,194
Estimated Fair Value		73,571
2029 Convertible Notes
Debt Instrument [Line Items]
Unamortized Debt Issuance Costs and Debt Discount/Premium	(5,783)	(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	(5,783)	(6,893)
Recorded Value	224,217	223,107
Estimated Fair Value	220,594	225,780
September 2030 Notes
Debt Instrument [Line Items]
Unamortized Debt Issuance Costs and Debt Discount/Premium	(6,360)	$ 0
September 2030 Notes | Notes
Debt Instrument [Line Items]
Outstanding Balance	350,000
Unamortized Debt Issuance Costs and Debt Discount/Premium	(6,360)
Recorded Value	343,640
Estimated Fair Value	$ 346,856

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