Variable Interest Entities Text Tag (Details) (USD $)	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2014		Sep. 30, 2011	Dec. 30, 2010	May 15, 2009	Apr. 28, 2006	Mar. 31, 2014 Carver Statutory Trust 1 [Member]		Mar. 31, 2013 Carver Statutory Trust 1 [Member]	Mar. 31, 2014 CDE 10 [Member]		Mar. 31, 2008 CDE 10 [Member]	Mar. 31, 2014 CDE 1-9, CDE 11-12 [Member]		Dec. 31, 2010 CDE 1-9, CDE 11-12 [Member]
Entity Information [Line Items]
Variable Interest Entity, Funded Exposure, Debt Investment		$ 13,000,000						$ 13,000,000		$ 13,000,000	$ 0			$ 0
Variable Interest Entity, Funded Exposure, Equity Invesment		0	[1]					400,000	[1]	400,000	0	[1]		0	[1]
% of Carver Statutory Trust I owned	100.00%
Cash					6,700,000
New Markets Tax Credit Award				25,000,000		65,000,000	59,000,000
Variable Interest Entity, Rights Transferred		149,000,000				40,000,000		0			19,000,000		19,000,000	40,000,000
Stockholders' Equity Attributable to Noncontrolling Interest																$ 6,700,000

[1] (1) Excludes any proceeds realized from exchange of equity interest in CDEs as detailed below.