EMPLOYEE BENEFIT PLANS - Additional Information (Details) - USD ($)	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised (in shares)	6,000	20,000	58,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options granted	0	0	0
Stock options \| Trust Company \| President and Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based Compensation Expense		$ 44,000
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 401,000	348,000
Stock based Compensation Expense	$ 319,000	$ 352,000	$ 302,000
Number of stock awards granted	69,285	90,763
Shares cancelled	20,976
Restricted stock \| Weighted average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year 6 months 10 days	1 year 7 months 17 days
Performance Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock awards granted	54,011	71,310
Shares cancelled	16,559
Time Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock awards granted	15,274	19,453
Shares cancelled	4,417
Retirement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses related to plan	$ 529,000	$ 525,000	$ 561,000
Directors' and Executive Officers' Deferred Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation plan annual interest rate	2.97%	3.61%	4.46%
Aggregate liability under the plan	$ 237,000	$ 312,000
Stock Option Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term	10 years
Vesting period	Zero to five years
Number of shares reserved for common stock	1,800,000
Unrecognized compensation expense	$ 0
Stock based Compensation Expense	0	0	$ 0
Total intrinsic value of stock options exercised	$ 25,000	$ 68,000	$ 238,000
Stock Option Plans \| President and Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options granted	500
Stock Option Plans \| Trust Company \| President and Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options granted	0	0	0
Stock options exercised (in shares)	500	500

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Represents period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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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