v2.4.1.9

Summary of Financial Instruments for Which Fair Value Option Has Been Elected (Detail) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Equity and Preferred Securities | $ 103,971 bx_EquityAndPreferredSecurities |  | $ 102,907 bx_EquityAndPreferredSecurities |
Total Assets | 6,444,914 us-gaap_AssetsFairValueDisclosure |  | 6,760,099 us-gaap_AssetsFairValueDisclosure |
Total Liabilities | 6,933,747 us-gaap_LiabilitiesFairValueDisclosure |  | 6,797,104 us-gaap_LiabilitiesFairValueDisclosure |
Corporate Bonds |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets of Consolidated CLO Vehicles: Corporate Bonds | 322,696 bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure / us-gaap_InvestmentTypeAxis = us-gaap_CorporateBondSecuritiesMember |  | 292,690 bx_AssetsOfConsolidatedCloVehiclesCorporateBondsFairValueDisclosure / us-gaap_InvestmentTypeAxis = us-gaap_CorporateBondSecuritiesMember |
Senior Secured Notes | Liabilities of Consolidated CLO Vehicles |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair value of Notes | 6,587,954 us-gaap_NotesPayableFairValueDisclosure / us-gaap_FairValueByLiabilityClassAxis = bx_LiabilitiesOfConsolidatedCloVehiclesMember / us-gaap_InvestmentTypeAxis = us-gaap_SeniorNotesMember | [1] | 6,448,352 us-gaap_NotesPayableFairValueDisclosure / us-gaap_FairValueByLiabilityClassAxis = bx_LiabilitiesOfConsolidatedCloVehiclesMember / us-gaap_InvestmentTypeAxis = us-gaap_SeniorNotesMember | [1]
Subordinated Notes | Liabilities of Consolidated CLO Vehicles |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair value of Notes | 345,793 us-gaap_NotesPayableFairValueDisclosure / us-gaap_FairValueByLiabilityClassAxis = bx_LiabilitiesOfConsolidatedCloVehiclesMember / us-gaap_InvestmentTypeAxis = us-gaap_SeniorSubordinatedNotesMember | [1] | 348,752 us-gaap_NotesPayableFairValueDisclosure / us-gaap_FairValueByLiabilityClassAxis = bx_LiabilitiesOfConsolidatedCloVehiclesMember / us-gaap_InvestmentTypeAxis = us-gaap_SeniorSubordinatedNotesMember | [1]
Other |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets of Consolidated CLO Vehicles: Other | 75,387 bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure / us-gaap_UnderlyingAssetClassAxis = us-gaap_CollateralizedSecuritiesOtherMember |  | 44,513 bx_AssetsOfConsolidatedCloVehiclesOtherFairValueDisclosure / us-gaap_UnderlyingAssetClassAxis = us-gaap_CollateralizedSecuritiesOtherMember |
Loans And Receivables |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Loans and Receivables | 40,691 us-gaap_LoansReceivableFairValueDisclosure / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = bx_LoansAndReceivablesMember |  | 40,397 us-gaap_LoansReceivableFairValueDisclosure / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = bx_LoansAndReceivablesMember |
Corporate Loans |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Assets of Consolidated CLO Vehicles: Corporate Loans | $ 5,902,169 bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |  | $ 6,279,592 bx_AssetsOfConsolidatedCloVehiclesCorporateLoansFairValueDisclosure / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |
[1] | Pursuant to GAAP consolidation guidance, the Partnership is required to consolidate all VIEs in which it has been identified as the primary beneficiary, including certain CLO vehicles, and other funds in which a consolidated entity of the Partnership, as the general partner of the fund, is presumed to have control. While the Partnership is required to consolidate certain funds, including CLO vehicles, for GAAP purposes, the Partnership has no ability to utilize the assets of these funds and there is no recourse to the Partnership for their liabilities since these are client assets and liabilities.

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- Definition Assets Of Consolidated CLO Vehicles Corporate Bonds Fair Value Disclosure + References No definition available. + Details
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- Definition Assets Of Consolidated CLO Vehicles Corporate Loans Fair Value Disclosure + References No definition available. + Details
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- Definition Assets Of Consolidated CLO Vehicles Other Fair Value Disclosure + References No definition available. + Details
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- Definition Equity and Preferred Securities Fair Value Disclosure + References No definition available. + Details
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Glossary Loan -URI http://asc.fasb.org/extlink&oid=6517073 + Details
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- Definition Fair value portion of notes payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19,20,22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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Balance Type: | credit
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- Details
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