Variable Interest Entities VIE (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Dec. 31, 2012	May 15, 2009
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	$ 5,850
Variable Interest Entity, Rights Transferred	149,000	40,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets	33,349
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	119,894
Variable Interest Entity, Total Involvment with SPE Asset	153,242
Variable Interest Entity, Funded Exposure, Debt Investment	13,000
Variable Interest Entity, Funded Exposure, Equity Invesment	0
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	50,310
Variable Interest Entity, Total Exposure	63,719
Carver Statutory Trust 1 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	0
Variable Interest Entity, Rights Transferred	0
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	13,400
Variable Interest Entity, Total Involvment with SPE Asset	13,400
Variable Interest Entity, Funded Exposure, Debt Investment	13,000
Variable Interest Entity, Funded Exposure, Equity Invesment	400
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	0
Variable Interest Entity, Total Exposure	13,400
CDE 1-9, CDE 11-12 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	0
Variable Interest Entity, Rights Transferred	40,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets	33,349
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	0
Variable Interest Entity, Total Involvment with SPE Asset	33,349
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	0
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	7,800
Variable Interest Entity, Total Exposure	7,800
CDE 10 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	1,700
Variable Interest Entity, Rights Transferred	19,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	15,992
Variable Interest Entity, Total Involvment with SPE Asset	15,992
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	0
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	7,410
Variable Interest Entity, Total Exposure	7,410
CDE 13 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	500
Variable Interest Entity, Rights Transferred	10,500
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	10,568
Variable Interest Entity, Total Involvment with SPE Asset	10,568
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	1
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	4,095
Variable Interest Entity, Total Exposure	4,096
CDE 14 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	400
Variable Interest Entity, Rights Transferred	10,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	10,004
Variable Interest Entity, Total Involvment with SPE Asset	10,004
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	1
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	3,900
Variable Interest Entity, Total Exposure	3,901
CDE 15, 16, 17 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	900
Variable Interest Entity, Rights Transferred	20,500
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	20,901
Variable Interest Entity, Total Involvment with SPE Asset	20,901
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	2
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	7,995
Variable Interest Entity, Total Exposure	7,997
CDE 18 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	600
Variable Interest Entity, Rights Transferred	13,254
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	13,282
Variable Interest Entity, Total Involvment with SPE Asset	13,282
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	1
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	5,169
Variable Interest Entity, Total Exposure	5,170
CDE 19 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	500
Variable Interest Entity, Rights Transferred	10,746
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	10,855
Variable Interest Entity, Total Involvment with SPE Asset	10,855
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	1
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	4,191
Variable Interest Entity, Total Exposure	4,192
CDE 20 [Member]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	625
Variable Interest Entity, Rights Transferred	12,500
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	12,419
Variable Interest Entity, Total Involvment with SPE Asset	12,419
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	1
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	4,875
Variable Interest Entity, Total Exposure	4,876
CDE21 [Domain]
Entity Information [Line Items]
Variable Interest Entity, Initial Consolidation, Gain (Loss)	625
Variable Interest Entity, Rights Transferred	12,500
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	12,471
Variable Interest Entity, Total Involvment with SPE Asset	12,471
Variable Interest Entity, Funded Exposure, Debt Investment	0
Variable Interest Entity, Funded Exposure, Equity Invesment	1
Variable Ineterest Entity, Unfunded Exposure, Funding Commitments	0
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	4,875
Variable Interest Entity, Total Exposure	$ 4,876