v3.25.2

Cover - USD ($)	12 Months Ended
Cover - USD ($)	Mar. 31, 2025	Jul. 15, 2025	Sep. 30, 2024
Cover [Abstract]
Document Type	10-K/A
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2025
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2025
Current Fiscal Year End Date	--03-31
Entity File Number	001-13007
Entity Registrant Name	CARVER BANCORP, INC.
Entity Central Index Key	0001016178
Entity Tax Identification Number	13-3904174
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	75 West 125th Street
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10027
City Area Code	718
Local Phone Number	230-2900
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	CARV
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 9,810,678
Entity Common Stock, Shares Outstanding		5,074,283
Document Financial Statement Error Correction [Flag]	false
Auditor Name	BDO USA, LLP
Auditor Location	New York
Auditor Firm ID	243

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument.

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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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The aggregate market value of the voting and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was last sold, or the average bid and asked price of such common equity, as of the last business day of the registrant's most recently completed second fiscal quarter.

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Local phone number for entity.

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Title of a 12(b) registered security.

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CARVER BANCORP INC 10-K/A