v2.4.1.9

Related Party Transactions - Additional Information (Detail) (USD $) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2015 | Mar. 31, 2014 | Dec. 31, 2014
Related Party Transaction [Line Items] |  |  |
Founder's, other senior managing directors' and employees' investments | $ 1,000,000,000 bx_InvestmentByFounderSeniorManagingDirectorsAndEmployees |  | $ 1,000,000,000 bx_InvestmentByFounderSeniorManagingDirectorsAndEmployees
Founder's, other senior managing directors' and employees' share of the Net Income Attributable to Redeemable Non-Controlling Interests | 53,100,000 bx_FoundersOtherSeniorManagingDirectorsAndEmployeesShareOfNetIncomeAttributableToRedeemableNonControllingAndNonControllingInterestsInConsolidatedEntities | 44,900,000 bx_FoundersOtherSeniorManagingDirectorsAndEmployeesShareOfNetIncomeAttributableToRedeemableNonControllingAndNonControllingInterestsInConsolidatedEntities |
Management and Advisory Fees, Net from Affiliates | 47,763,000 us-gaap_RevenueFromRelatedParties | 74,032,000 us-gaap_RevenueFromRelatedParties |
Interest from loans to affiliates | 2,000,000 bx_InterestFromLoansToAffiliates | 100,000 bx_InterestFromLoansToAffiliates |
Partnership Unit to Blackstone Common Unit ratio | 100.00%bx_LimitedPartnershipToCommonStockConversionRatio |  |
Cash saving in tax receivable agreements, percentage | 85.00%bx_CashSavingInTaxReceivableAgreements |  |
Expected future payments under the tax receivable agreements | 1,200,000,000 bx_ExpectedFuturePaymentsUnderTaxReceivableAgreements |  |
Expected future payments under the tax receivable agreements in years | 15 years |  |
After-tax net present value estimated payments | $ 370,400,000 bx_AfterTaxNetPresentValueEstimatedPaymentsForTaxReceivableAgreements |  |
After-tax net present value discount rate assumption | 15.00%bx_AfterTaxNetPresentValueDiscountRateAssumptionForTaxReceivableAgreements |  |

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- Definition After Tax Net Present Value Estimated Payments For The Tax Receivable Agreements + References No definition available. + Details
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- Definition Expected future payments under the tax receivable agreements + References No definition available. + Details
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- Definition Expected future payments under the tax receivable agreements in years + References No definition available. + Details
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- Definition Founders Other Senior Managing Directors And Employees Share Of Net Income Attributable To Redeemable Non Controlling And Non Controlling Interests In Consolidated Entities. + References No definition available. + Details
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- Definition Interest From Loans to Affiliates + References No definition available. + Details
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- Definition Investment By Founder Senior Managing Directors And Employees + References No definition available. + Details
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- Details
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- Definition Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Related Parties -URI http://asc.fasb.org/extlink&oid=16382449 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07.1(c)) -URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 07 -Paragraph b -Subparagraph 1 -Article 6 + Details
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