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Summary of Fair Value by Strategy Type Alongside Consolidated Funds of Hedge Funds' Remaining Unfunded Commitments and Ability to Redeem Such Investments (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2013
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Net Asset Value As Fair Value By Strategy [Line Items] |  |
Fair Value | $ 1,116,749 |
Unfunded Commitments | 6,905 |
Diversified Instruments |  |
Net Asset Value As Fair Value By Strategy [Line Items] |  |
Fair Value | 139,008 | [1]
Unfunded Commitments | 4,925 | [1]
Credit Driven |  |
Net Asset Value As Fair Value By Strategy [Line Items] |  |
Fair Value | 195,787 | [2]
Unfunded Commitments | 1,980 | [2]
Event Driven |  |
Net Asset Value As Fair Value By Strategy [Line Items] |  |
Fair Value | 110,442 | [3]
Equity |  |
Net Asset Value As Fair Value By Strategy [Line Items] |  |
Fair Value | 611,919 | [4]
Commodities |  |
Net Asset Value As Fair Value By Strategy [Line Items] |  |
Fair Value | $ 59,593 | [5]
[1] | Diversified Instruments include investments in funds that invest across multiple strategies. Investments representing 59% of the fair value of the investments in this category may not be redeemed at, or within three months of, the reporting date. Investments representing 34% of the fair value of the investments in this category represent investments in hedge funds that are in the process of liquidating. Distributions from these funds will be received as underlying investments are liquidated. The time at which this redemption restriction may lapse cannot be estimated. The remaining 7% of investments in this category are redeemable as of the reporting date. As of the reporting date, the investee fund manager had elected to side-pocket 21% of Blackstone's investments in this category.
[2] | The Credit Driven category includes investments in hedge funds that invest primarily in domestic and international bonds. Investments representing 94% of the fair value of the investments in this category may not be redeemed at, or within three months of, the reporting date. Investments representing 6% of the total fair value in the credit driven category are subject to redemption restrictions at the discretion of the investee fund manager who may choose (but may not have exercised such ability) to side-pocket such investments. As of the reporting date, the investee fund manager had not elected to side-pocket any of Blackstone's investments in this category.
[3] | The Event Driven category includes investments in hedge funds whose primary investing strategy is to identify certain event-driven investments. Withdrawals are not permitted in this category. Distributions will be received as the underlying investments are liquidated.
[4] | The Equity category includes investments in hedge funds that invest primarily in domestic and international equity securities. Investments representing 76% of the total fair value of investments in this category may not be redeemed at, or within three months of, the reporting date. Investments representing 16% of the total fair value of investments in this category are subject to lock-up restrictions. Investments representing 7% of the total fair value of investments in this category are subject to redemption restrictions at the discretion of the investee fund manager who may choose (but may not have elected such ability) to side-pocket such investments or gate such investments, whereby limiting the amount of withdrawals from the fund during a redemption period. Investments representing 1% of the total fair value of investments in this category are in hedge funds that are in the process of liquidating. As of the reporting date, the investee fund manager had elected to side-pocket 1% of Blackstone's investments in this category.
[5] | The Commodities category includes investments in commodities-focused funds that primarily invest in futures and physical-based commodity driven strategies. Investments in this category may not be redeemed at, or within three months of, the reporting date.

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- Definition The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25499696&loc=SL6742756-110258 + Details
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