Derivatives and Hedging Fair Value of Derivative Assets (Details 1) - Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member] - USD ($) $ in Thousands	Dec. 31, 2016	Mar. 31, 2016
Derivative
Derivative Asset, Fair Value, Gross Asset		$ 1,933
Derivative Asset, Fair Value, Gross Liability		(963)
Derivative Asset		970
Derivative Asset, Not Subject to Master Netting Arrangement		7,680
Derivative Asset, Collateral, Obligation to Return Cash, Offset		1,840
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		10,490
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset		0
Derivative Asset, Fair Value, Gross Liability		0
Derivative Asset		0
Derivative Asset, Not Subject to Master Netting Arrangement		7,599
Derivative Asset, Collateral, Obligation to Return Cash, Offset		0
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		7,599
Not Designated as Hedging Instrument [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset	$ 113	1,933
Derivative Asset, Fair Value, Gross Liability	(14)	(963)
Derivative Asset	99	970
Derivative Asset, Not Subject to Master Netting Arrangement	737	81
Derivative Asset, Collateral, Obligation to Return Cash, Offset	4,376	1,840
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	5,212	2,891
Not Designated as Hedging Instrument [Member] \| Foreign Exchange Forward [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset	113	1,933
Derivative Asset, Fair Value, Gross Liability	(14)	(963)
Derivative Asset	99	970
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	99	970
Not Designated as Hedging Instrument [Member] \| Future [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset	0
Derivative Asset, Fair Value, Gross Liability	0
Derivative Asset	0
Derivative Asset, Not Subject to Master Netting Arrangement	737
Derivative Asset, Collateral, Obligation to Return Cash, Offset	4,376
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	$ 5,113
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivative
Derivative Asset, Fair Value, Gross Asset		0
Derivative Asset, Fair Value, Gross Liability		0
Derivative Asset		0
Derivative Asset, Not Subject to Master Netting Arrangement		81
Derivative Asset, Collateral, Obligation to Return Cash, Offset		1,840
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		$ 1,921

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
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226052-175313

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

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