v2.4.1.9

Investments (Detail) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
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Schedule of Investments [Line Items] |  |
Investments of Consolidated Blackstone Funds | $ 11,123,132 bx_InvestmentsOfConsolidatedFunds | $ 11,375,407 bx_InvestmentsOfConsolidatedFunds
Equity Method Investments | 3,144,959 us-gaap_EquityMethodInvestments | 3,240,825 us-gaap_EquityMethodInvestments
Blackstone's Treasury Cash Management Strategies | 1,631,696 bx_InvestmentsInTreasuryCashManagementStrategies | 1,666,061 bx_InvestmentsInTreasuryCashManagementStrategies
Performance Fees | 6,842,398 bx_PerformanceFeesReceivable | 6,337,045 bx_PerformanceFeesReceivable
Other Investments | 154,069 us-gaap_OtherInvestments | 146,251 us-gaap_OtherInvestments
Investments | $ 22,896,254 us-gaap_Investments | $ 22,765,589 us-gaap_Investments

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