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BORROWINGS - Issued and Outstanding SBA Debentures (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Debt Instrument [Line Items]
Debenture Amount	$ 1,148,000	$ 969,875
SBA Debentures \| Unsecured Debt
Debt Instrument [Line Items]
Debenture Amount	$ 223,000	$ 175,000
Weighted average interest rate	4.43%	4.40%	4.18%
Debentures due September 2031 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	1.575%
Debenture Amount	$ 15,000
Debentures due March 2032 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	3.209%
Debenture Amount	$ 25,000
Debentures due September 2032 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	4.435%
Debenture Amount	$ 40,000
Debentures due March 2033 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	5.215%
Debenture Amount	$ 40,000
Debentures due September 2033 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	5.735%
Debenture Amount	$ 10,000
Debentures due March 2034 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	5.164%
Debenture Amount	$ 15,000
Debentures due December 2034 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	4.509%
Debenture Amount	$ 8,000
Debentures due March 2035 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	5.092%
Debenture Amount	$ 22,000
Debentures due March 2036 \| Unsecured Debt
Debt Instrument [Line Items]
Fixed Interest Rate	4.973%
Debenture Amount	$ 40,000
Small Business Administration Debentures Due, March 2026 \| Unsecured Debt
Debt Instrument [Line Items]
Debenture Amount	$ 8,000
Weighted average interest rate	4.52%