|
Performance Fees Allocated to Funds (Detail) (USD $)
In Thousands, unless otherwise specified
|
3 Months Ended |
|
Mar. 31, 2015
|
| Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
|
| Performance Fees, December 31, 2014 |
$ 6,337,045bx_PerformanceFeesReceivable |
| Performance Fees Allocated as a Result of Changes in Fund Fair Values |
1,643,458bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues |
| Foreign Exchange Loss |
(43,947)bx_ForeignCurrencyExchangeGainLoss |
| Fund Distributions |
(1,094,158)bx_FundDistributions |
| Performance Fees, March 31, 2015 |
6,842,398bx_PerformanceFeesReceivable |
| Private Equity Segment |
|
| Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
|
| Performance Fees, December 31, 2014 |
2,215,584bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_PrivateEquitySegmentMember |
| Performance Fees Allocated as a Result of Changes in Fund Fair Values |
949,515bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues
/ us-gaap_StatementBusinessSegmentsAxis
= bx_PrivateEquitySegmentMember |
| Fund Distributions |
(402,044)bx_FundDistributions
/ us-gaap_StatementBusinessSegmentsAxis
= bx_PrivateEquitySegmentMember |
| Performance Fees, March 31, 2015 |
2,763,055bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_PrivateEquitySegmentMember |
| Real Estate Segment |
|
| Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
|
| Performance Fees, December 31, 2014 |
3,721,751bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_RealEstateSegmentMember |
| Performance Fees Allocated as a Result of Changes in Fund Fair Values |
674,475bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues
/ us-gaap_StatementBusinessSegmentsAxis
= bx_RealEstateSegmentMember |
| Foreign Exchange Loss |
(43,947)bx_ForeignCurrencyExchangeGainLoss
/ us-gaap_StatementBusinessSegmentsAxis
= bx_RealEstateSegmentMember |
| Fund Distributions |
(666,321)bx_FundDistributions
/ us-gaap_StatementBusinessSegmentsAxis
= bx_RealEstateSegmentMember |
| Performance Fees, March 31, 2015 |
3,685,958bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_RealEstateSegmentMember |
| Hedge Fund Solutions Segment |
|
| Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
|
| Performance Fees, December 31, 2014 |
15,031bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_HedgeFundSolutionsSegmentMember |
| Performance Fees Allocated as a Result of Changes in Fund Fair Values |
12,353bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues
/ us-gaap_StatementBusinessSegmentsAxis
= bx_HedgeFundSolutionsSegmentMember |
| Fund Distributions |
(12,696)bx_FundDistributions
/ us-gaap_StatementBusinessSegmentsAxis
= bx_HedgeFundSolutionsSegmentMember |
| Performance Fees, March 31, 2015 |
14,688bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_HedgeFundSolutionsSegmentMember |
| Credit Segment |
|
| Schedule of Performance Fees and Allocations to the General Partner [Line Items] |
|
| Performance Fees, December 31, 2014 |
384,679bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_CreditSegmentMember |
| Performance Fees Allocated as a Result of Changes in Fund Fair Values |
7,115bx_PerformanceFeesAllocatedAsResultOfChangesInFundFairValues
/ us-gaap_StatementBusinessSegmentsAxis
= bx_CreditSegmentMember |
| Fund Distributions |
(13,097)bx_FundDistributions
/ us-gaap_StatementBusinessSegmentsAxis
= bx_CreditSegmentMember |
| Performance Fees, March 31, 2015 |
$ 378,697bx_PerformanceFeesReceivable
/ us-gaap_StatementBusinessSegmentsAxis
= bx_CreditSegmentMember |