JUNIOR SUBORDINATED DEBENTURES (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022
JUNIOR SUBORDINATED DEBENTURES
Amount Outstanding	$ 27,836
Fair value adjustment	(918)
Total Debentures	$ 26,918	$ 26,833
Riverview Bancorp Statutory Trust I
JUNIOR SUBORDINATED DEBENTURES
Issuance Date	Dec. 01, 2005
Amount Outstanding	$ 7,217
Rate Type	Variable
Initial Rate	5.88%
Current Rate	6.23%
Maturity Date	3/2036
Riverview Bancorp Statutory Trust II
JUNIOR SUBORDINATED DEBENTURES
Issuance Date	Jun. 01, 2007
Amount Outstanding	$ 15,464
Rate Type	Variable
Initial Rate	7.03%
Current Rate	6.22%
Maturity Date	9/2037
Merchants Bancorp Statutory Trust I
JUNIOR SUBORDINATED DEBENTURES
Issuance Date	Jun. 01, 2003
Amount Outstanding	$ 5,155
Rate Type	Variable
Initial Rate	4.16%
Current Rate	8.23%
Maturity Date	6/2033

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Date the debt instrument was issued, in YYYY-MM-DD format.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

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