INVESTMENT SECURITIES - Additional information (Details) - USD ($) $ in Thousands	9 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Mar. 31, 2024
INVESTMENT SECURITIES
Proceeds from the sale of investment securities	$ 0	$ 0
Gross realized gains on sales of investment securities	0	$ 0
Available for sale with amortized cost	144,814		$ 164,416
Available for sale, at estimated fair value	124,874		143,196
Held to maturity, estimated fair value	180,474		195,519
Asset Pledged as Collateral \| Government public funds held by the bank
INVESTMENT SECURITIES
Available for sale with amortized cost	2,200		2,600
Available for sale, at estimated fair value	2,000		2,400
Held to maturity at amortized cost	10,500		11,200
Held to maturity, estimated fair value	8,600		9,300
Asset Pledged as Collateral \| FHLB and FRB Borrowing Arrangements
INVESTMENT SECURITIES
Held to maturity at amortized cost	143,400		151,200
Held to maturity, estimated fair value	$ 119,600		$ 126,100

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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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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Amount excluding accrued interest, 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 excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity), classified as current.

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

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The cash inflow associated with the sale of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

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