BORROWINGS - Contractual Payment Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Mar. 31, 2024
Debt Instrument [Line Items]
2025	$ 0
2026	140,000
2027	150,000
2028	0
2029	349,875
Thereafter	153,000
Total	792,875	$ 779,875
SBA Debentures \| Unsecured Debt
Debt Instrument [Line Items]
2025	0
2026	0
2027	0
2028	0
2029	0
Thereafter	153,000
Total	153,000
Corporate Credit Facility \| Line of Credit
Debt Instrument [Line Items]
2025	0
2026	0
2027	0
2028	0
2029	200,000
Thereafter	0
Total	200,000
SPV Credit Facility \| Line of Credit \| Secured Debt
Debt Instrument [Line Items]
2025	0
2026	0
2027	0
2028	0
2029	78,000
Thereafter	0
Total	78,000	0
January 2026 Notes \| Notes
Debt Instrument [Line Items]
2025	0
2026	140,000
2027	0
2028	0
2029	0
Thereafter	0
Total	140,000	140,000
October 2026 Notes \| Notes
Debt Instrument [Line Items]
2025	0
2026	0
2027	150,000
2028	0
2029	0
Thereafter	0
Total	150,000	150,000
August 2028 Notes \| Notes
Debt Instrument [Line Items]
2025	0
2026	0
2027	0
2028	0
2029	71,875
Thereafter	0
Total	$ 71,875	$ 71,875

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