Consolidated Statement of Changes in Stockholders' Equity (USD $)	Total	Preferred Stock [Member]		Common Stock [Member]		Additional Paid-in Capital [Member]		Treasury Stock [Member]		Noncontrolling Interest [Member]		Accumulated deficit [Member]		Accumulated Other Comprehensive Income (Loss) [Member]
Stockholders' Equity at Mar. 31, 2011	$ 27,717,000	$ 18,980,000		$ 25,000		$ 27,026,000		$ (569,000)		$ 4,038,000		$ (21,464,000)		$ (319,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) / income attributable to Carver Bancorp, Inc.	(23,407,000)	0		0		0		0		0		(23,407,000)		0
Other comprehensive income (loss), net of tax	478,000	0		0		0		0		0		0		478,000
Transfer between Non-controlling and Controlling Interest	0	0		0		1,973,000		0		(1,973,000)		0		0
Income attributable to non-controlling interest	686,000	0		0		0		0		686,000		0		0
Accrued Preferred Dividends Paid	(364,000)	0		0		0		0		0		(364,000)		0
Accrued Preferred Dividends	0	0		0		(144,000)		0		0		144,000		0
Net (loss) / income attributable to non-controlling interest	629,000
Conversion of Stock, Amount Issued	0	(18,980,000)		24,000		18,956,000		0		0		0		0
Stock Issued During Period, Value, Conversion of Convertible Securities	51,428,000	45,118,000		12,000		6,298,000		0		0		0		0
Treasury stock activity	81,000	0		0		(41,000)		122,000		0		0		0
Stockholders' Equity at Mar. 31, 2012	56,619,000	45,118,000		61,000		54,068,000		(447,000)		2,751,000		(45,091,000)		159,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) / income attributable to Carver Bancorp, Inc.	662,000	0		0		0		0		0		662,000		0
Other comprehensive income (loss), net of tax	404,000	0		0		0		0		0		0		404,000
Transfer between Non-controlling and Controlling Interest	0	0		0		1,665,000		0		(1,665,000)		0		0
Net (loss) / income attributable to non-controlling interest	(945,000)	0		0		0		0		(945,000)		0		0
Treasury stock activity	(5,000)	0		0		(25,000)		30,000		0		(10,000)		0
Stockholders' Equity at Mar. 31, 2013	56,735,000	45,118,000		61,000		55,708,000		(417,000)		141,000		(44,439,000)		563,000
Pension plan adjustment	(1,148,000)	0	[1]	0	[1]	0	[1]	0	[1]	0	[1]	716,000	[1]	(716,000)	[1]
OCI adjustment related to pension	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) / income attributable to Carver Bancorp, Inc.	(836,000)	0		0		0		0		0		(836,000)		0
Other comprehensive income (loss), net of tax	(4,615,000)	0		0		0		0		0		0		(4,615,000)
Transfer between Non-controlling and Controlling Interest	0	0		0		400,000		0		(400,000)		0		0
Net (loss) / income attributable to non-controlling interest	(110,000)	0		0		0		0		(110,000)		0		0
Treasury stock activity	(5,000)	0		0		6,000		0		0		(11,000)		0
Stockholders' Equity at Mar. 31, 2014	$ 51,169,000	$ 45,118,000		$ 61,000		$ 56,114,000		$ (417,000)		$ (369,000)		$ (44,570,000)		$ (4,768,000)

[1] (1) Adjustment reflected within total equity relating to the accounting for pension plans under ASC 715-30. Refer to notes 1, 13 and 18 for further detail.