Premises and Equipment - Schedule of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Mar. 31, 2023
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 14,674	$ 13,902
Less accumulated depreciation	10,414	9,798
Total premises and equipment	4,260	4,104
Land
Property, Plant and Equipment [Line Items]
Premises and equipment	838	818
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment	9,294	8,855
Equipment
Property, Plant and Equipment [Line Items]
Premises and equipment	3,370	3,150
Automobiles
Property, Plant and Equipment [Line Items]
Premises and equipment	136	48
Computer software
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 1,036	$ 1,031