v2.4.0.8

Offsetting of Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Offsetting Assets and Liabilities [Line Items] |  |
Gross and Net Amounts of Assets Presented in the Statement of Financial Condition | $ 159,327 | $ 303,362
Gross Amounts Not Offset in the Statement of Financial Condition, Financial Instruments | 151,419 | 252,001
Gross Amounts Not Offset in the Statement of Financial Condition, Cash Collateral Received | 582 | 36,748
Asset Net Amount | 7,326 | 14,613
Gross And Net Amounts Of Liabilities Presented In the Statement Of Financial Condition | 320,634 | 146,463
Gross Amount of Liabilities Not Offset in the Statement of Financial Condition, Financial Instruments | 319,377 | 146,249
Cash Collateral Pledged | 1,257 |
Liability Net Amount |  | 214
Freestanding Derivatives |  |
Offsetting Assets and Liabilities [Line Items] |  |
Gross and Net Amounts of Assets Presented in the Statement of Financial Condition | 10,343 | 55,344
Gross Amounts Not Offset in the Statement of Financial Condition, Financial Instruments | 3,025 | 3,983
Gross Amounts Not Offset in the Statement of Financial Condition, Cash Collateral Received | 582 | 36,748
Asset Net Amount | 6,736 | 14,613
Gross And Net Amounts Of Liabilities Presented In the Statement Of Financial Condition | 4,282 | 4,197
Gross Amount of Liabilities Not Offset in the Statement of Financial Condition, Financial Instruments | 3,025 | 3,983
Cash Collateral Pledged | 1,257 |
Liability Net Amount |  | 214
Reverse Repurchase Agreements |  |
Offsetting Assets and Liabilities [Line Items] |  |
Gross and Net Amounts of Assets Presented in the Statement of Financial Condition | 148,984 | 248,018
Gross Amounts Not Offset in the Statement of Financial Condition, Financial Instruments | 148,394 | 248,018
Asset Net Amount | 590 |
Repurchase Agreements |  |
Offsetting Assets and Liabilities [Line Items] |  |
Gross And Net Amounts Of Liabilities Presented In the Statement Of Financial Condition | 316,352 | 142,266
Gross Amount of Liabilities Not Offset in the Statement of Financial Condition, Financial Instruments | $ 316,352 | $ 142,266

X
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X
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Balance Type: | debit
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X
- Definition Gross Amount of Financial and Derivative Assets Not Offset in the Statement of Financial Condition, Financial Instruments + References No definition available. + Details
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- Definition Gross Amount of Liabilities Not Offset in the Statement of Financial Condition, Financial Instruments. + References No definition available. + Details
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- Definition Liability Net Amount + References No definition available. + Details
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Namespace Prefix: | bx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
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Period Type: | duration