Fair Value of Derivative Assets (Details 1) - Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Derivative
Derivative Asset, Fair Value, Gross Asset	$ 655	$ 856
Derivative Asset, Fair Value, Gross Liability	(21)	(276)
Derivative Asset	634	580
Derivative Asset, Not Subject to Master Netting Arrangement	9,357	5,462
Derivative Asset, Collateral, Obligation to Return Cash, Offset	3,332	0
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	13,323	6,042
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Asset, Fair Value, Gross Liability	0	0
Derivative Asset	0	0
Derivative Asset, Not Subject to Master Netting Arrangement	7,259	5,462
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	7,259	5,462
Not Designated as Hedging Instrument [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset	655	856
Derivative Asset, Fair Value, Gross Liability	(21)	(276)
Derivative Asset	634	580
Derivative Asset, Not Subject to Master Netting Arrangement	2,098	0
Derivative Asset, Collateral, Obligation to Return Cash, Offset	3,332	0
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	6,064	580
Not Designated as Hedging Instrument [Member] \| Foreign Exchange Forward [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset	655	781
Derivative Asset, Fair Value, Gross Liability	(21)	(259)
Derivative Asset	634	522
Derivative Asset, Not Subject to Master Netting Arrangement	0	0
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	634	522
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset	0	75
Derivative Asset, Fair Value, Gross Liability	0	(17)
Derivative Asset	0	58
Derivative Asset, Not Subject to Master Netting Arrangement	2,098	0
Derivative Asset, Collateral, Obligation to Return Cash, Offset	3,332	0
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	$ 5,430	$ 58

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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