Derivatives and Hedging Fair Value of Derivative Liabilities (Details) - Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member] - USD ($) $ in Thousands	Jun. 30, 2016	Mar. 31, 2016
Derivative
Derivative Liability, Fair Value, Gross Liability	$ (5,400)
Derivative Liability, Fair Value, Gross Asset	2,182
Derivative Liability	(3,218)
Derivative Liability, Not Subject to Master Netting Arrangement	(6,522)
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	12,076
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	2,336
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative
Derivative Liability, Fair Value, Gross Liability	0
Derivative Liability, Fair Value, Gross Asset	0
Derivative Liability	0
Derivative Liability, Not Subject to Master Netting Arrangement	(4,369)
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	4,740
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	371
Not Designated as Hedging Instrument [Member]
Derivative
Derivative Liability, Fair Value, Gross Liability	(5,400)	$ (16,364)
Derivative Liability, Fair Value, Gross Asset	2,182	280
Derivative Liability	(3,218)	(16,084)
Derivative Liability, Not Subject to Master Netting Arrangement	(2,153)	(1,995)
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	7,336	5,920
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	1,965	(12,159)
Not Designated as Hedging Instrument [Member] \| Foreign Exchange Forward [Member]
Derivative
Derivative Liability, Fair Value, Gross Liability	(5,400)	(16,364)
Derivative Liability, Fair Value, Gross Asset	2,182	280
Derivative Liability	(3,218)	(16,084)
Derivative Liability, Not Subject to Master Netting Arrangement	0	0
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(3,218)	(16,084)
Not Designated as Hedging Instrument [Member] \| Future [Member]
Derivative
Derivative Liability, Fair Value, Gross Liability	0
Derivative Liability, Fair Value, Gross Asset	0
Derivative Liability	0
Derivative Liability, Not Subject to Master Netting Arrangement	(2,153)
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	7,336
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	$ 5,183
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivative
Derivative Liability, Fair Value, Gross Liability		0
Derivative Liability, Fair Value, Gross Asset		0
Derivative Liability		0
Derivative Liability, Not Subject to Master Netting Arrangement		(1,995)
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		5,920
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		$ 3,925

Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value, after the effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

+ References

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-Publisher FASB
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- Definition

Fair value of asset associated with financial liability or 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.

+ References

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Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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Fair value of financial liability or 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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