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FAIR VALUE MEASUREMENTS - Estimated Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Mar. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Transfers of assets from level 1 to level 2 | $ 0 | $ 0
Transfers of assets from level 2 to level 1 | 0 | 0
Transfers of assets into level 3 | 0 | 0
Transfers of assets out of level 3 | 0 | 0
Recurring basis |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 118,447 | 119,436
Recurring basis | Municipal securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 31,841 | 31,019
Recurring basis | Agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 30,934 | 30,203
Recurring basis | Real estate mortgage investment conduits |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 22,890 | 23,490
Recurring basis | Residential mortgage-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 9,169 | 10,226
Recurring basis | Other mortgage-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 23,613 | 24,498
Recurring basis | Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 118,447 | 119,436
Recurring basis | Level 2 | Municipal securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 31,841 | 31,019
Recurring basis | Level 2 | Agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 30,934 | 30,203
Recurring basis | Level 2 | Real estate mortgage investment conduits |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 22,890 | 23,490
Recurring basis | Level 2 | Residential mortgage-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | 9,169 | 10,226
Recurring basis | Level 2 | Other mortgage-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total assets measured at fair value on a recurring basis | $ 23,613 | $ 24,498

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