Carver Bancorp Inc.-Parent Company Only-Condensed Statements of Financial Condition (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Condensed Balance Sheet Statements, Captions [Line Items]
Other assets	$ 12,182	$ 7,156
Total assets	723,224	735,314
Other liabilities	13,308	21,768
Total liabilities	678,000	680,227
Stockholders' Equity Attributable to Parent	45,224	55,087	$ 52,301
Total liabilities and equity	723,224	735,314
Parent Company
Condensed Balance Sheet Statements, Captions [Line Items]
Cash on deposit with subsidiaries	668	1,433	$ 12,374
Investment in subsidiaries	62,453	70,646
Other assets	123	66
Total assets	63,244	72,145
Borrowings	15,903	15,903
Accounts Payable and Other Accrued Liabilities	1,475	499
Other liabilities	642	656
Total liabilities	18,020	17,058
Stockholders' Equity Attributable to Parent	45,224	55,087
Total liabilities and equity	$ 63,244	$ 72,145