Off-Balance Sheet Financial Instruments and Guarantees (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020
Loss Contingencies [Line Items]
Financial instrument commitments	$ 224,760	$ 127,631
Commitments to grant loans [Member]
Loss Contingencies [Line Items]
Financial instrument commitments	82,444	55,036
Unfunded commitments under lines of credit [Member]
Loss Contingencies [Line Items]
Financial instrument commitments	136,710	68,530
Standby letters of credit [Member]
Loss Contingencies [Line Items]
Financial instrument commitments	$ 5,606	$ 4,065