v2.4.0.6

Realized and Net Change in Unrealized Gains (Losses) on Investments Held by Blackstone's Treasury Cash Management Strategies (Detail) (Blackstone's Treasury Cash Management Strategies, USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2012 | Jun. 30, 2011 | Jun. 30, 2012 | Jun. 30, 2011
Blackstone's Treasury Cash Management Strategies |  |  |  |
Gain (Loss) on Investments [Line Items] |  |  |  |
Realized Gains | $ 2,167 | $ 1,321 | $ 10 | $ 1,020
Net Change in Unrealized Gains (Losses) | 5,245 | 1,592 | 826 | 2,221
Total realized and net change in unrealized gains (losses) | $ 7,412 | $ 2,913 | $ 836 | $ 3,241

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