v2.4.1.9

Partnership's Borrowings Through Consolidated CLO Vehicles (Detail) (Partnership's Borrowings Through Consolidated CLO Vehicles, USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2015 | Dec. 31, 2014
Debt Instrument [Line Items] |  |  |  |
Borrowing Outstanding | $ 7,430,059 us-gaap_DebtInstrumentCarryingAmount |  | $ 7,334,316 us-gaap_DebtInstrumentCarryingAmount |
Senior Secured Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Borrowing Outstanding | 6,705,220 us-gaap_DebtInstrumentCarryingAmount / us-gaap_InvestmentTypeAxis = us-gaap_SeniorNotesMember / us-gaap_LongtermDebtTypeAxis = bx_PartnershipBorrowingsThroughConsolidatedCollateralizedLoanObligationVehiclesMember |  | 6,594,266 us-gaap_DebtInstrumentCarryingAmount / us-gaap_InvestmentTypeAxis = us-gaap_SeniorNotesMember / us-gaap_LongtermDebtTypeAxis = bx_PartnershipBorrowingsThroughConsolidatedCollateralizedLoanObligationVehiclesMember |
Weighted Average Interest Rate | 1.52%us-gaap_DebtWeightedAverageInterestRate / us-gaap_InvestmentTypeAxis = us-gaap_SeniorNotesMember / us-gaap_LongtermDebtTypeAxis = bx_PartnershipBorrowingsThroughConsolidatedCollateralizedLoanObligationVehiclesMember |  | 1.27%us-gaap_DebtWeightedAverageInterestRate / us-gaap_InvestmentTypeAxis = us-gaap_SeniorNotesMember / us-gaap_LongtermDebtTypeAxis = bx_PartnershipBorrowingsThroughConsolidatedCollateralizedLoanObligationVehiclesMember |
Weighted Average Remaining Maturity in Years | 3 years 3 months 18 days |  | 3 years 9 months 18 days |
Subordinated Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Borrowing Outstanding | $ 724,839 us-gaap_DebtInstrumentCarryingAmount / us-gaap_InvestmentTypeAxis = us-gaap_SeniorSubordinatedNotesMember / us-gaap_LongtermDebtTypeAxis = bx_PartnershipBorrowingsThroughConsolidatedCollateralizedLoanObligationVehiclesMember |  | $ 740,050 us-gaap_DebtInstrumentCarryingAmount / us-gaap_InvestmentTypeAxis = us-gaap_SeniorSubordinatedNotesMember / us-gaap_LongtermDebtTypeAxis = bx_PartnershipBorrowingsThroughConsolidatedCollateralizedLoanObligationVehiclesMember |
Weighted Average Interest Rate |  | [1] |  | [1]
[1] | The Subordinated Notes do not have contractual interest rates but instead receive distributions from the excess cash flows of the CLO vehicles.

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- Definition Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -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 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 + Details
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