BORROWINGS - Contractual Payment Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025
Debt Instrument [Line Items]
2026	$ 0
2027	150,000
2028	0
2029	383,875
2030	230,000
Thereafter	175,000
Outstanding Balance	938,875	$ 969,875
SBA Debentures \| Unsecured Debt
Debt Instrument [Line Items]
2026	0
2027	0
2028	0
2029	0
2030	0
Thereafter	175,000
Outstanding Balance	175,000	175,000
Corporate Credit Facility \| Line of Credit \| Corporate Credit Facility
Debt Instrument [Line Items]
2026	0
2027	0
2028	0
2029	200,000
2030	0
Thereafter	0
Outstanding Balance	200,000	235,000
SPV Credit Facility \| Line of Credit \| SPV Credit Facility
Debt Instrument [Line Items]
2026	0
2027	0
2028	0
2029	112,000
2030	0
Thereafter	0
Outstanding Balance	112,000	108,000
October 2026 Notes \| Notes
Debt Instrument [Line Items]
2026	0
2027	150,000
2028	0
2029	0
2030	0
Thereafter	0
Outstanding Balance	150,000	150,000
August 2028 Notes \| Notes
Debt Instrument [Line Items]
2026	0
2027	0
2028	0
2029	71,875
2030	0
Thereafter	0
Outstanding Balance	71,875	71,875
2029 Convertible Notes \| Convertible Debt
Debt Instrument [Line Items]
2026	0
2027	0
2028	0
2029	0
2030	230,000
Thereafter	0
Outstanding Balance	$ 230,000	$ 230,000

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