Document and Entity Information Document - shares	9 Months Ended
	Dec. 31, 2016	Feb. 16, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	CARVER BANCORP INC
Entity Central Index Key	0001016178
Current Fiscal Year End Date	--03-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		3,696,087
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes