v2.4.1.9

Information for Financial Instruments on Which Fair Value Option was Elected (Detail) (USD $)	Mar. 31, 2015		Dec. 31, 2014
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	$ (93,521,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue		$ (210,717,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue
Fair value of financial instruments more than one day past due	2,875,000bx_FairValueOfFinancialInstrumentsMoreThanOneDayPastDue	[1]	4,369,000bx_FairValueOfFinancialInstrumentsMoreThanOneDayPastDue	[1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due	(25,514,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceedsFairValueMoreThanOneDayPastDue	[1]	(21,876,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceedsFairValueMoreThanOneDayPastDue	[1]
Corporate Bonds
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	(2,324,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateBondSecuritiesMember		(7,814,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateBondSecuritiesMember
Fair value of financial instruments more than one day past due	0bx_FairValueOfFinancialInstrumentsMoreThanOneDayPastDue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateBondSecuritiesMember		0bx_FairValueOfFinancialInstrumentsMoreThanOneDayPastDue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateBondSecuritiesMember
Loans And Receivables
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	(7,273,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = bx_LoansAndReceivablesMember		(5,323,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = bx_LoansAndReceivablesMember
Fair value of financial instruments more than one day past due			0bx_FairValueOfFinancialInstrumentsMoreThanOneDayPastDue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = bx_LoansAndReceivablesMember
Corporate Loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Uncollected principal balance on financial instruments that exceeded fair value total	(83,924,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		(197,580,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceededFairValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair value of financial instruments more than one day past due	2,875,000bx_FairValueOfFinancialInstrumentsMoreThanOneDayPastDue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]	4,369,000bx_FairValueOfFinancialInstrumentsMoreThanOneDayPastDue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]
Uncollected principal balance on financial instruments that exceeds fair value more than one day past due	$ (25,514,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceedsFairValueMoreThanOneDayPastDue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]	$ (21,876,000)bx_UncollectedPrincipalBalanceOnFinancialInstrumentsThatExceedsFairValueMoreThanOneDayPastDue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]
[1] Corporate Loans and Corporate Bonds within CLO assets are classified as past due if contractual payments are more than one day past due.

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- Definition

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- Definition

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- Definition

Uncollected Principal Balance On Financial Instruments That Exceeded Fair Value More than One Day Past Due

+ References

No definition available.

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