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Investments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Investment [Line Items]
Investments	$ 22,242,040		$ 22,242,040		$ 20,377,031
Recognized net gains related to equity method investments	72,300	$ 165,600	227,700	$ 328,100
Equity investments, carrying value	$ 48,900		$ 48,900
Patria Investments Limited and Patria Investimentos Ltda.
Investment [Line Items]
Equity method investment, percentage	40.00%		40.00%
Consolidated Blackstone Funds
Investment [Line Items]
Investments	$ 8,633,794		$ 8,633,794		8,376,338
Consolidated Blackstone Funds \| Blackstone
Investment [Line Items]
Investments	$ 383,900		$ 383,900		$ 366,500