INVESTMENT SECURITIES - Held to maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 39,225	$ 39,574
Gross Unrealized Gains	36
Gross Unrealized Losses	(597)	(1,354)
Estimated Fair Value	38,664	38,220
Municipal securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	10,384	10,391
Gross Unrealized Gains	36
Gross Unrealized Losses	(177)	(509)
Estimated Fair Value	10,243	9,882
Agency securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	7,676	7,688
Gross Unrealized Losses	(105)	(220)
Estimated Fair Value	7,571	7,468
Real estate mortgage investment conduits
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	9,068	9,207
Gross Unrealized Losses	(77)	(141)
Estimated Fair Value	8,991	9,066
Residential mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	5,989	6,175
Gross Unrealized Losses	(75)	(119)
Estimated Fair Value	5,914	6,056
Other mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	6,108	6,113
Gross Unrealized Losses	(163)	(365)
Estimated Fair Value	$ 5,945	$ 5,748

Amount of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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