INVESTMENT SECURITIES - Available for sale (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 267,512	$ 216,514
Gross Unrealized Gains	2,755	2,301
Gross Unrealized Losses	(1,414)	(2,511)
Estimated Fair Value	268,853	216,304
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	38,293	23,883
Gross Unrealized Gains	434	238
Gross Unrealized Losses	(213)	(555)
Estimated Fair Value	38,514	23,566
Agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	47,076	25,996
Gross Unrealized Gains	69	5
Gross Unrealized Losses	(392)	(686)
Estimated Fair Value	46,753	25,315
Real estate mortgage investment conduits
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	53,997	55,826
Gross Unrealized Gains	374	469
Gross Unrealized Losses	(411)	(480)
Estimated Fair Value	53,960	55,815
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	85,259	71,787
Gross Unrealized Gains	948	1,075
Gross Unrealized Losses	(349)	(614)
Estimated Fair Value	85,858	72,248
Other mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	42,887	39,022
Gross Unrealized Gains	930	514
Gross Unrealized Losses	(49)	(176)
Estimated Fair Value	$ 43,768	$ 39,360

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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Amount, before tax, of unrealized loss 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 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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Amount 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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