Carver Bancorp Inc.- Parent Company Only-Condensed Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Condensed Income Statements, Captions [Line Items]
Grant income	$ 439	$ 2,089
Interest expense on borrowings	1,203	509
Salaries and employee benefits	13,186	11,516
Shareholder expense	373	344
Other	7,199	7,209
Net loss	(4,401)	(847)
Comprehensive loss	(9,954)	(4,334)
Parent Company
Condensed Income Statements, Captions [Line Items]
Equity in net loss from subsidiaries	(2,640)	706
Other income	27	17
Grant income	439	60
Total (loss) income	(2,174)	783
Interest expense on borrowings	839	481
Salaries and employee benefits	712	232
Shareholder expense	155	162
Other	521	755
Total expense	2,227	1,630
Net loss	$ (4,401)	$ (847)