Quarterly Financial Data Quarterly Financial Data (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended							12 Months Ended			3 Months Ended
	Mar. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2013 Scenario, Previously Reported [Member]	Dec. 31, 2013 Restatement Adjustment [Member]
Interest income	$ 5,733	$ 5,942	$ 5,569	$ 5,590	$ 5,927	$ 6,117	$ 6,151	$ 23,248	$ 23,785	$ 27,936	$ 6,004	$ 6,004
Interest expense	(986)	(977)	(1,009)	(1,094)	(1,210)	(1,253)	(1,321)	(3,951)	(4,878)	(8,053)	(979)	(979)
Net interest income	4,747	4,965	4,560	4,496	4,717	4,864	4,830	19,297	18,907	19,883	5,025	5,025
Provision for loan losses	(300)	505	(831)	3,713	398	(560)	(224)	(426)	(3,327)	16,342	1,052	1,052
Non-interest income	1,889	1,577	2,130	1,134	2,541	2,434	940	6,806	7,049	3,654	1,210	1,210
Non-interest expense	(7,243)	(6,599)	(5,280)	(8,411)	(7,304)	(6,890)	(6,633)	27,373	29,238	30,934	(7,535)	(8,251)
Income tax expense (benefit)	(8)	(16)	(72)	(64)	(68)	(37)	(159)	102	328	(961)	(6)	(6)
Net (loss) / income attributable to non-controlling interest	146	(90)	(93)	(181)	190	51	885	(110)	(945)	629	147	147
Net (loss) / income attributable to Carver Bancorp, Inc.	$ (769)	$ 342	$ 414	$ 687	$ 474	$ (138)	$ (361)	$ (836)	$ 662	$ (23,407)	$ (107)	$ (823)
Earnings Per Share, Basic	$ (0.21)	$ 0.09	$ 0.11	$ 0.19	$ 0.13	$ (0.04)	$ (0.10)	$ (0.23)	$ 0.18	$ (14.26)	$ (0.03)	$ (0.22)
Earnings Per Share, Diluted	$ (0.21)	$ 0.09	$ 0.11	$ 0.19	$ 0.13			$ (0.23)	$ 0.18	$ (14.26)	$ (0.03)	$ (0.22)