Line items represent reporting 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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Investments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Investment [Line Items]
Investments	$ 19,763,563		$ 24,434,049
Recognized net gains related to equity method investments	$ 162,500	$ 168,500
Patria Investments Limited and Patria Investimentos Ltda.
Investment [Line Items]
Equity method investment, percentage	40.00%
Consolidated Blackstone Funds
Investment [Line Items]
Investments	$ 7,560,831		12,954,121
Consolidated Blackstone Funds \| Blackstone
Investment [Line Items]
Investments	$ 348,700		$ 488,400