VARIABLE INTEREST ENTITIES AND CONSOLIDATION OF INVESTMENT VEHICLES (Details 4) (CIVs, USD $) In Thousands	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010
Fair Value Assets and Liabilities Measured on Recurring Basis Financial Statement Unobservable Input Level 3
Total realized and unrealized gains (losses), net	$ (21,675)
Significant unobservable inputs (Level 3)
Fair Value Assets and Liabilities Measured on Recurring Basis Financial Statement Unobservable Input Level 3
Assets measured at fair value using significant unobservable inputs, value at beginning of period	26,066	9,226
Purchases, sales, issuances and settlements, net , assets	13,246	5,046
Net transfer into/out of Level 3, assets	5,862	10,414
Realized and unrealized gains/(losses), net, assets	6,977	1,380
Assets measured at fair value using significant unobservable inputs, value at end of period	52,151	26,066
Unrealized gains (losses) on Level 3 assets and liabilities still held at the reporting date	(21,688)	1,377
Significant unobservable inputs (Level 3) \| Hedge funds
Fair Value Assets and Liabilities Measured on Recurring Basis Financial Statement Unobservable Input Level 3
Assets measured at fair value using significant unobservable inputs, value at beginning of period	12,374	4,250
Purchases, sales, issuances and settlements, net , assets	8,340	(3,670)
Net transfer into/out of Level 3, assets	5,862	10,414
Realized and unrealized gains/(losses), net, assets	7,696	1,380
Assets measured at fair value using significant unobservable inputs, value at end of period	34,272	12,374
Significant unobservable inputs (Level 3) \| Private equity funds
Fair Value Assets and Liabilities Measured on Recurring Basis Financial Statement Unobservable Input Level 3
Assets measured at fair value using significant unobservable inputs, value at beginning of period	13,692	4,976
Purchases, sales, issuances and settlements, net , assets	4,906	8,716
Realized and unrealized gains/(losses), net, assets	(719)
Assets measured at fair value using significant unobservable inputs, value at end of period	17,879	13,692
Significant unobservable inputs (Level 3) \| CLO debt
Fair Value Assets and Liabilities Measured on Recurring Basis Financial Statement Unobservable Input Level 3
Net transfers into/out of Level 3, liabilities	(249,668)
Realized and unrealized gains/(losses), net	(28,652)
Liabilities measured at fair value using significant unobservable inputs, value at end of period	$ (278,320)

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This element represents total gains or (losses) for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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This element represents total gains or losses for the period (unrealized), arising from assets and liabilities still held at the reporting date measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(1)

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This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(2)

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This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
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This element represents total gains or losses for the period (realized and unrealized), arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
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This element represents [net] transfers in to and out of liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

+ References

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(3)

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