Variable Interest Entities VIE (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		3 Months Ended
	Jun. 30, 2012	May 15, 2009	Jun. 30, 2012 Carver Statutory Trust 1 [Member]	Jun. 30, 2012 CDE 1-9, CDE 11-12 [Member]	Jun. 30, 2012 CDE 10 [Member]	Jun. 30, 2012 CDE 13 [Member]	Jun. 30, 2012 CDE 14 [Member]	Jun. 30, 2012 CDE 15, 16, 17 [Member]	Jun. 30, 2012 CDE 18 [Member]	Jun. 30, 2012 CDE 19 [Member]	Jun. 30, 2012 CDE 20 [Member]	Mar. 31, 2012 CDE 20 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	$ 5,225		$ 0	$ 0	$ 1,700	$ 500	$ 400	$ 900	$ 600	$ 500	$ 625
Variable Interest Entity, Rights Transferred	136,500	40,000	0	40,000	19,000	10,500	10,000	20,500	13,254	10,746	12,500	12,500
Variable Interest Entity, Consolidated, Carrying Amount, Assets	33,443		0	33,443	0	0	0	0	0	0	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	108,178		13,400	0	16,673	10,576	10,064	20,878	13,282	10,841	12,464
Variable Interest Entity, Total Involvment with SPE Asset	141,621		13,400	33,443	16,673	10,576	10,064	20,878	13,282	10,841	12,464
Variable Interest Entity, Funded Exposure, Debt Investment	13,000		13,000	0	0	0	0	0	0	0	0
Variable Interest Entity, Funded Exposure, Equity Invesment	407		400	0	0	1	1	2	1	1	1
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0		0	0	0	0	0	0	0	0	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	45,435		0	7,800	7,410	4,095	3,900	7,995	5,169	4,191	4,875
Variable Interest Entity, Total Exposure	$ 58,842		$ 13,400	$ 7,800	$ 7,410	$ 4,096	$ 3,901	$ 7,997	$ 5,170	$ 4,192	$ 4,876