Common Stock Dividends	3 Months Ended
	Jun. 30, 2020
Dividends [Abstract]
Stockholders' Equity Note Disclosure	COMMON STOCK DIVIDENDS        On October 28, 2011, the Treasury exchanged the CDCI Series B preferred stock for 2,321,286 shares of Carver common stock and the Series C preferred stock converted into 1,208,039 shares of Carver common stock and 45,118 shares of Series D preferred stock. Series C stock was previously reported as mezzanine equity, and upon conversion to common and Series D preferred stock is now reported as equity attributable to Carver Bancorp, Inc. The holders of the Series D Preferred Stock are entitled to receive dividends, on an as-converted basis, simultaneously to the payment of any dividends on the common stock.In June 2020, an institutional investor notified the Company of their intention to effect a series of transfers of up to all its holdings of Series D Preferred Stock. As of June 30, 2020, 597 shares of Series D Preferred Stock were converted into 73,003 shares of Common Stock, which were subsequently sold in the open market. The conversion and sale had no impact on the Company's total capital.