Regulatory Capital Requirements - Schedule of Actual Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)
Total Capital (to Risk- Weighted Assets), Actual Amount	$ 66,949	$ 47,809
Tier 1 Capital (to Risk- Weighted Assets), Actual Amount	62,278	43,355
Common Equity Tier 1 Capital to Risk-Weighted Assets, Actual Amount	62,278	43,355
Tier 1 Capital (to Average Assets), Actual Amount	$ 62,278	$ 43,355
Total Capital (to Risk- Weighted Assets), Actual Ratio	0.1798	0.1345
Tier 1 Capital (to Risk- Weighted Assets), Actual Ratio	0.1673	0.122
Common Equity Tier 1 Capital to Risk-Weighted Assets, Actual Ratio	0.1673	0.122
Tier 1 Capital (to Average Assets), Actual Ratio	0.1377	0.1012
Total Capital (to Risk- Weighted Assets), Minimum Required for Capital Adequacy Purposes, Amount	$ 29,782	$ 28,432
Tier 1 Capital (to Risk- Weighted Assets), Minimum Required for Capital Adequacy Purposes, Amount	22,337	21,324
Common Equity Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes, Amount	16,753	15,993
Tier 1 Capital (to Average Assets), Minimum Required for Capital Adequacy Purposes, Amount	$ 18,091	$ 17,139
Total Capital (to Risk- Weighted Assets), Minimum Required for Capital Adequacy Purposes, Ratio	0.08	0.08
Tier 1 Capital (to Risk- Weighted Assets), Minimum Required for Capital Adequacy Purposes, Ratio	0.06	0.06
Common Equity Tier 1 Capital to Risk-Weighted Assets, Minimum Required for Capital Adequacy Purposes, Ratio	0.045	0.045
Tier 1 Capital (to Average Assets), Minimum Required for Capital Adequacy Purposes, Ratio	0.04	0.04
Total Capital (to Risk- Weighted Assets), Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Amount	$ 37,228	$ 35,540
Tier 1 Capital (to Risk- Weighted Assets), Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Amount	29,782	28,432
Common Equity Tier 1 Capital to Risk-Weighted Assets, Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Amount	24,198	23,101
Tier 1 Capital (to Average Assets), Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Amount	$ 22,614	$ 21,424
Total Capital (to Risk- Weighted Assets), Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Ratio	0.10	0.10
Tier 1 Capital (to Risk- Weighted Assets), Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Ratio	0.08	0.08
Common Equity Tier 1 Capital to Risk-Weighted Assets, Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Ratio	0.065	0.065
Tier 1 Capital (to Average Assets), Minimum Required To be Well-Capitalized Under Prompt Corrective Action Provisions, Ratio	0.05	0.05