INVESTMENT SECURITIES - Available for sale (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Mar. 31, 2023
INVESTMENT SECURITIES
Amortized Cost	$ 225,156	$ 235,591
Gross Unrealized Gains	57	43
Gross Unrealized Losses	(31,229)	(24,135)
Estimated Fair Value	193,984	211,499
Municipal securities
INVESTMENT SECURITIES
Amortized Cost	47,752	47,857
Gross Unrealized Gains	52	16
Gross Unrealized Losses	(10,149)	(7,612)
Estimated Fair Value	37,655	40,261
Agency securities
INVESTMENT SECURITIES
Amortized Cost	89,088	91,858
Gross Unrealized Gains		23
Gross Unrealized Losses	(7,541)	(5,974)
Estimated Fair Value	81,547	85,907
Real estate mortgage investment conduits
INVESTMENT SECURITIES
Amortized Cost	32,751	34,247
Gross Unrealized Losses	(6,940)	(5,370)
Estimated Fair Value	25,811	28,877
Residential mortgage-backed securities
INVESTMENT SECURITIES
Amortized Cost	14,905	16,512
Gross Unrealized Gains	1
Gross Unrealized Losses	(1,439)	(1,041)
Estimated Fair Value	13,467	15,471
Other mortgage-backed securities
INVESTMENT SECURITIES
Amortized Cost	40,660	45,117
Gross Unrealized Gains	4	4
Gross Unrealized Losses	(5,160)	(4,138)
Estimated Fair Value	$ 35,504	$ 40,983

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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