Summary of Status of Partnership's Unvested Equity-Based Awards (Detail)	3 Months Ended
Mar. 31, 2016 $ / shares shares
Blackstone \| Blackstone Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance \| shares	40,901,755
Granted (Units) \| shares	363,239
Vested (Units) \| shares	(4,089,498)
Forfeited (Units) \| shares	(164,898)
Ending Balance \| shares	37,010,598
Beginning Balance \| $ / shares	$ 32.98
Granted (Weighted-Average Grant Date Fair Value) \| $ / shares	28.57
Vested (Weighted-Average Grant Date Fair Value) \| $ / shares	22.46
Forfeited (Weighted-Average Grant Date Fair Value) \| $ / shares	39.21
Ending Balance \| $ / shares	34.07
Blackstone Group L P \| Equity Settled Awards Weighted Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance \| $ / shares	22.38
Granted (Weighted-Average Grant Date Fair Value) \| $ / shares	28.77
Vested (Weighted-Average Grant Date Fair Value) \| $ / shares	22.92
Forfeited (Weighted-Average Grant Date Fair Value) \| $ / shares	20.04
Ending Balance \| $ / shares	23.23
Blackstone Group L P \| Cash Settled Awards Weighted Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance \| $ / shares	28.79
Granted (Weighted-Average Grant Date Fair Value) \| $ / shares	29.24
Vested (Weighted-Average Grant Date Fair Value) \| $ / shares	28.14
Ending Balance \| $ / shares	$ 28.84
Blackstone Group L P \| Equity Settled Awards Deferred Restricted Common Units And Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance \| shares	14,342,129
Granted (Units) \| shares	1,893,628
Vested (Units) \| shares	(2,600,563)
Forfeited (Units) \| shares	(271,587)
Ending Balance \| shares	13,363,607
Blackstone Group L P \| Cash Settled Awards Phantom Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance \| shares	27,942
Granted (Units) \| shares	2,465
Vested (Units) \| shares	(529)
Ending Balance \| shares	29,878

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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