v2.4.0.8

Summary of Aggregate Notional Amount and Fair Value of Derivative Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Derivative Assets, Notional | $ 2,427,718 | $ 1,306,817
Derivative Liabilities, Notional | 1,379,602 | 1,035,631
Derivative Assets, Fair Value | 80,642 | 99,374
Derivative Liabilities, Fair Value | 19,380 | 22,070
Freestanding Derivatives | Interest Rate Contracts | Blackstone - Other |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Assets, Notional | 1,914,476 | 689,300
Derivative Liabilities, Notional | 1,035,600 | 636,555
Derivative Assets, Fair Value | 44,545 | 55,270
Derivative Liabilities, Fair Value | 4,673 | 4,116
Freestanding Derivatives | Interest Rate Contracts | Investment Of Consolidated CLO Vehicles |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Assets, Notional | 81,505 | 165,517
Derivative Liabilities, Notional |  | 90,500
Derivative Assets, Fair Value | 3,653 | 6,132
Derivative Liabilities, Fair Value |  | 772
Freestanding Derivatives | Foreign Currency Contracts | Blackstone - Other |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Assets, Notional | 68,896 | 16,771
Derivative Liabilities, Notional | 66,115 | 7,025
Derivative Assets, Fair Value | 1,490 | 74
Derivative Liabilities, Fair Value | 1,398 | 81
Freestanding Derivatives | Foreign Currency Contracts | Investment Of Consolidated CLO Vehicles |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Assets, Notional | 362,841 | 435,229
Derivative Liabilities, Notional | 236,887 | 301,551
Derivative Assets, Fair Value | 30,954 | 37,898
Derivative Liabilities, Fair Value | 8,775 | 17,101
Freestanding Derivatives | Credit Default Swaps | Blackstone - Other |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liabilities, Notional | 41,000 |
Derivative Liabilities, Fair Value | $ 4,534 |

X
- Definition Nominal or face amount used to calculate payments on the derivative asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Notional Amount -URI http://asc.fasb.org/extlink&oid=6519104 + Details
Name: | us-gaap_DerivativeAssetNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value before effects of master netting arrangements, of a 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226000-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226000-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Nominal or face amount used to calculate payments on the derivative liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Notional Amount -URI http://asc.fasb.org/extlink&oid=6519104 + Details
Name: | us-gaap_DerivativeLiabilityNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativesFairValueLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration