v2.4.1.9

Components of Other Assets (Detail) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
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Schedule of Other Assets [Line Items] |  |
Furniture, Equipment and Leasehold Improvements, Net | $ 132,448 us-gaap_PropertyPlantAndEquipmentNet | $ 135,740 us-gaap_PropertyPlantAndEquipmentNet
Prepaid Expenses | 220,192 us-gaap_PrepaidExpenseCurrentAndNoncurrent | 102,503 us-gaap_PrepaidExpenseCurrentAndNoncurrent
Other Assets | 102,998 us-gaap_OtherAssetsMiscellaneous | 96,501 us-gaap_OtherAssetsMiscellaneous
Freestanding Derivatives | 2,406 bx_FreestandingDerivatives | 3,290 bx_FreestandingDerivatives
Net Investment Hedges |  | 523 us-gaap_NetInvestmentHedgeDerivativeAssetsAtFairValue
Total Other Assets | $ 458,044 us-gaap_OtherAssets | $ 338,557 us-gaap_OtherAssets

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