v2.4.0.8

Related Party Transactions - Additional Information (Detail) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2013 | Dec. 31, 2011 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Related Party Transaction [Line Items] |  |  |  |  |
Founder's, other senior managing directors' and employees' investments | $ 1,000,000,000 |  | $ 1,000,000,000 | $ 939,400,000 |
Founder's, other senior managing directors' and employees' share of the Net Income Attributable to Redeemable Non-Controlling Interests |  |  | 224,700,000 | 114,100,000 | 109,400,000
Management and Advisory Fees, Net from Affiliates |  |  | 253,900,000 | 254,700,000 | 317,700,000
Interest from loans to affiliates |  |  | 3,400,000 | 4,400,000 | 3,700,000
Partnership Unit to Blackstone Common Unit ratio |  |  | 1 |  |
Cash saving in tax receivable agreements, percentage |  |  | 85.00% |  |
Reduction in due to pre IPO owners and others resulted from change in effective tax rate of corporate tax payers | 20,500,000 | 197,800,000 |  |  |
Expected future payments under the tax receivable agreements | 1,200,000,000 |  | 1,200,000,000 |  |
Expected future payments under the tax receivable agreements in years | 15 years |  | 15 years |  |
After-tax net present value estimated payments | 407,400,000 |  | 407,400,000 |  |
After-tax net present value discount rate assumption | 15.00% |  | 15.00% |  |
Payments made under tax receivable agreements and related tax benefits |  |  |  | $ 80,600,000 |

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